ACU-302 Series

CHAPTER 2

MAINTENANCE

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I- SERVICING

1- PERIODIC MAINTENANCE Periodic maintenance and lubrication intervals are listed in Chart 1. Service major component assemblies, including the engine and generator, in accordance with the component manufacturer’s instructions contained in Chapter 5 and as described below. Performance of these procedures at the intervals suggested will assure long and dependable unit operation. Observe the following safety precautions and warnings during service procedures:

WARNING: KEEP BODY AND CLOTHING AWAY FROM ROTATING MACHINERY AND BELTS. ALWAYS TURN OFF UNIT BATTERY SWITCH BEFORE PERFORMING ANY WORK ON THE UNIT TO PREVENT INJURY FROM ACCIDENTAL STARTING. NEVER DISASSEMBLE OR BRAZE A COMPONENT UNDER PRESSURE. RELIEVE THE PRESSURE FIRST. REFRIGERANT VAPORS ARE 4 TO 5 TIMES HEAVIER THAN AIR (96 PSIA AT 77°F). INHALATION OF CONCENTRATED VAPORS CAN BE FATAL. IN THE EVENT OF A LARGE SPILL OR LEAKAGE, VENTILATE THE AREA USING AUXILIARY VENTILATION IF NECESSARY TO DISSIPATE COLLECTED VAPORS. LIQUID REFRIGERANT HFC-134a BOILS AT -15°F. TO PREVENT FROST BITE, AVOID ALL SKIN AND EYE CONTACT. ALWAYS WEAR PROTECTIVE CLOTHING, LINED BUTYL GLOVES, AND CHEMICAL SPLASH EYE PROTECTION WHEN WORKING WITH REFRIGERANT. HFC-134a IS NONFLAMMABLE AT AMBIENT TEMPERATURES AND ATMOSPHERE PRESSURE. HOWEVER, HFC-134a IS COMBUSTIBLE AT PRESSURES AS LOW AS 5.5 PSIG AT 350°F WHEN MIXED WITH 60% OR GREATER CONCENTRATIONS OF AIR. NEVER LEAK TEST THE UNIT WITH A PRESSURIZED MIXTURE OF HFC-134a AND AIR. COMBUSTIBLE MIXTURES MAY FORM WHEN LIQUID HFC-134a IS PUMPED INTO A CLOSED VESSEL IF THE INITIAL AIR PRESSURE EXCEEDS ONE ATMOSPHERE (15 PSIG). NEVER EXPOSE AN HFC-134a CONTAINER TO A TEMPERATURE HIGHER THAN 125°F.

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EXERCISE EXTREME CARE WHEN TRANSPORTING AND HANDLING REFRIGERANT CONTAINERS. NEVER LIFT CONTAINERS WITH A SLING. AVOID EXPOSURE OF REFRIGERANT HFC-134a TO OPEN FLAME OR HOT SURFACES. DECOMPOSITION PRODUCES HYDROCHLORIC AND HYDROFLUORIC ACIDS. SOME CLEANERS, CHEMICALS, PAINTS AND PRIMERS HAVE ADVERSE EFFECTS ON SKIN, EYES, AND RESPIRATORY TRACT. OBSERVE MANUFACTURER’S WARNING LABELS, MATERIAL SAFETY DATA SHEET (MSDS), AND CURRENT SAFETY DIRECTIVES. USE ONLY IN AUTHORIZED AREAS. UNLESS OTHERWISE INDICATED, USE AS DESCRIBED IN THIS MANUAL SHOULD NOT RESULT IN HEALTH CONCERNS. IF UNIQUE LOCAL CONDITIONS MAKE COMPLIANCE WITH THE PROTECTIVE CLOTHING OR OTHER OCCUPATIONAL HEALTH REQUIREMENTS SPECIFIED IN THIS MANUAL UNNECESSARY OR IMPRACTICAL, OBTAIN AN EVALUATION FROM THE BIOENVIRONMENTAL ENGINEER AND BASE SAFETY OFFICE. EXERCISE CAUTION WHEN USING COMPRESSED AIR, SOLID PARTICLES PROPELLED BY COMPRESSED AIR MAY PRESENT A HAZARD TO USING PERSONNEL AND OTHERS. AIR PRESSURE SHOULD BE REDUCED TO LESS THAN 30 PSIG (207 kPa) AND USED WITH NIOSH APPROVED PROTECTIVE EQUIPMENT. USE INSULATED GLOVES WHEN HANDLING HEATED OR CHILLED PARTS. USE CORRECT LIFTING EQUIPMENT AND TECHNIQUES. NEVER WORK UNDER SUSPENDED LOADS. SPRING-LOADED MECHANISMS CAN CAUSE INJURY IF RELEASED IN AN UNCONTROLLED MANNER. ALWAYS EXERCISE CARE WHEN DISASSEMBLING SPRING-LOADED COMPONENTS. AVOID BREATHING FUMES FROM BRAZING OPERATIONS. BRAZE ONLY IN A WELL-VENTILATED AREA AND USE EYE PROTECTION. ENSURE THAT THE COMPONENT OR LINE BEING BRAZED/DEBRAZED IS FULLY DEPRESSURIZED AND VENTED TO ATMOSPHERE. AVOID CONTACT WITH HOT ENGINE PARTS. HOT ENGINE COOLANT CAN CAUSE SEVERE BURNS. EXERCISE EXTREME CAUTION WHEN SERVICING THE ENGINE COOLING SYSTEM.

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CAUTION: PROTECT THE ENVIRONMENT, RECOVER AND RECLAIM REFRIGERANT TO THE MAXIMUM EXTENT POSSIBLE WHEN SERVICING OR REPAIRING THE UNIT. THIS UNIT USES REFRIGERANT HFC-134a (TLD PART No. 1009272) AND TLD PART NO. 1053583 COMPRESSOR OIL. DO NOT INTRODUCE ANY OTHER REFRIGERANT OR OIL INTO THE REFRIGERATION SYSTEM. TO AVOID POSSIBLE EQUIPMENT DAMAGE, OPERATE THE EMERGENCY SHUT DOWN SYSTEM ONLY IN THE EVENT OF AN EMERGENCY. IF WELDING OR GRINDING ON GALVANIZED PARTS, SAFETY GLASSES AND A DUST FILTRATION MASK MUST BE WORN TO PREVENT EXPOSURE TO FUMES AND DUST. The following chart shows the frequency of maintenance required on the listed components.

Component Maintenance Required*1

Engine Air filter Check monthly. Replace as necessary.*2

Oil and filter Change the oil and filter every 500 hours or every 6 months.*3

Fuel filters Change every 500 hours or 6 months.*4 Hoses Replace all fuel and flexible hoses after 5 years

maximum service. Coolant Drain, flush the cooling system, and replace the

engine coolant every two years or 4,000 hours.*5 Fuel/water separator Drain water and sediment daily.

Valve lash Initially after 1,000 hours or 12 months; then every 2,000 hours or 2 years.

Fan hub Check every 1,000 hours or 12 months. Belt tensioner bearing Check every 1,000 hours or 12 months.

Vibration damper Inspect every 2,000 hours or 2 years.

*1 Reduction of the interval shown may be necessary under harsh operating conditions such as low engine temperature, excessively heavy loads, and high oil temperatures, or operation in particularly arid or dusty environments.

*2 The gauge installed on the engine air inlet indicates filter condition. Replace when red. *3 The use of high sulfur fuels will require reducing the time internal between oil changes.

Refer to the engine manufacturer’s instructions contained in Chapter 5 for maximum oil drain intervals when using high sulfur fuel. Change the oil and filter on new engines after the first 50 hours of operation and thereafter at 500 hour or 6-month intervals, whichever comes sooner.

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*4 Fill the filter elements with fresh, clean No. 2-D diesel fuel before installation. Bleed air from the fuel system after servicing by using the manual priming pump.

*5 Refill the engine cooling system with an all-season antifreeze solution.

NOTE: Engine cooling system capacity is 8.4 quarts (7.9 liters). The complete generator set cooling system capacity, including the radiator is 5.5 gallons (21 liters).

COMPONENT MAINTENANCE REQUIRED *1 Thermostats and gaskets

Replace the thermostats and gaskets every two years or 4,000 hours

Exhaust system Empty accumulated carbon deposits from the exhaust silencer every 6 months.

Exterior surfaces Clean the engine with fuel oil and dry with low pressure compressed air (max 30 psi) every 200 hours of operation.

Serpentine drive belt Check drive belt for excessive cracking every three months or 250 hours. Replace as necessary.

Trailer and Running Gear: Wheels and tires Rotate tire and wheel assemblies every 1,200 hours or

two years. Retighten lug nuts to the proper torque every 300 hours or at 6-month intervals.

Wheel hubs Repack bearings every two years. Adjust every 600 hours or annually.

Fifth wheel hub Repack bearings every two years. Adjust every 600 hours or annually

Refrigeration System: Condenser coil Clean monthly Evaporator coil Inspect annually and clean if required. *6 Refrigerant filter/drier Replace the desiccant cartridge and clean the filter

element when the filter pressure drop exceeds 3 psi or the system sight glass shows a pink indicator.

Delivery Air System: Air inlet filter Clean monthly. *7 Blower wheel and housing

Clean every 1,000 hours.

Blower motor bearings Lubricate every 6 months Condenser Fan Drive: Fan Motor bearings: Shaft end Lubricate annually. Opposite end Lubricate every 18 months

*6 The evaporator coil should require cleaning only if the unit has been operated with a

defective or missing blower inlet filter.

*7 Wash the filter in a mild soap and water solution, rinse, and air dry in a shaded location.

Chart 1- Lubrication and Maintenance

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CAUTION: DO NOT STEAM CLEAN THE ENGINE. THE USE OF ENGINE STEAM CLEANING EQUIPMENT RISKS EXPOSURE OF REFRIGERANT LINES AND VESSELS TO EXCESSIVE TEMPERATURES.

Refrigerant, lubricants and filters for periodic maintenance of the unit are listed below in Chart 2. The chart includes the name, TLD part number, and description of the item needed to maintain the unit. Additional information on specific lubricants may be found in the component manufacturer’s literature contained in Chapter 5. Additional filters may be found in the unit parts book or by calling your local TLD spare parts office.

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Nomenclature TLD Part No.

Vendor (Cage Code)

Vendor Part No.

Qty. per unit

Engine: Lube oil 1012342 -- 15W-40*1 AR

5 gallons(cool only

unit)

Coolant 1033604-50 -- --

7 gallons (heat/cool

unit) Refrigeration System:

Refrigerant HFC-134a 1009272*2 23037 R-134a AR*8 Compressor oil 1053583*3 -- -- AR Filter/drier element 1000473 28193 848-CM 1 Condenser fan motor bearings

UMG7-1 Chevron SR1 #2 AR

Heat transfer paste 1001788 00365 -- AR Insulation tape 1000491 87698 PT #1 AR Delivered Air System:

Air inlet filter 1030129 OUX52 1 Blower motor bearings UMG7-1 Chevron SR1 #2 AR Electrical System: Battery UML 4-1*4 00365 -- AR Electrical contacts Coml*5 00365 -- AR Trailer and Running Gear:

Wheel bearings UMG5-3*6 00365 -- AR Tow bar UMO1-9*7 00365 00 AR Enclosure: Latches and hinges UMO1-9*7 00365

*1 Fill to the “FULL” mark on the engine dipstick. *2 Pressurized liquid *3 Only TLD part No. 1053583 lubrication oil can be used in the compressor. The

introduction of any other oil will prove detrimental to the system and will void the warranty. *4 Terminal protector. *5 Contact cleaner. *6 Wheel bearing lubricant. *7 Lubricating oil. *8 Initial charge: 50 lbs.

Chart 2- Refrigerant, Lubricants, and Filters

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1…Tow Bar Pivot 5…Fuel gauge

2…Wheel Bearing 6…Radiator cap (through roof cutout)

3…Fuel fill cap 7…Condenser coil

4…Wheel and Tire Assembly 8…Electrical Contacts

PERIODIC MAINTENANCE

FIGURE 1

1

2 3

4

5

6 7

8

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9…Refrigerant filter/drier 12…Blower motor bearings

10…Air inlet filter 13…Condenser fan motor bearings

11…Evaporator coil

PERIODIC MAINTENANCE

FIGURE 2

9

10

11 12

13

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14…Primary Fuel Filter/Water separator 17…Alternator/Fan Drive Belt

15…Secondary Fuel Filter 18…Radiator Cap

16…Engine Oil Dipstick 19…Air Cleaner Dust Purge

PERIODIC MAINTENANCE

FIGURE 3

14

15 16

17

18

19

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20…Air Filter

21…Air Filter Restriction Indicator

22…Engine Oil Filter

23…Engine Starter Motor

24…12 VDC Battery Charging Alternator

PERIODIC MAINTENANCE

FIGURE 4

20

21

22

23

24

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A- ENGINE Engine maintenance shall be performed in accordance with the instructions provided by the engine manufacturer’s literature contained in Chapter 5 and the following instructions.

NOTE: Refer to the engine operator’s manual, contained in Chapter 5, for detailed servicing information, including more information on engine oil and filter replacement. (1) Lubrication Schedule

The time schedules indicated are approximate. They are based on average operating conditions. It may be necessary to reduce the times shown under harsh operating conditions such as low engine temperatures, excessively heavy loads, high oil temperatures, intermittent operation, and operation in particularly dusty environments (See Lubrication and Maintenance in this chapter).

(2) Oil Specification

Engine oil recommended by the manufacturer is identified by the API (American Petroleum Institute) Classification CH,CI, or higher. Further information on oil specifications is contained in the manufacturer’s literature contained in Chapter 5.

(3) Oil Viscosity

The use of 15W-40 grade oil is recommended for year round service. Further information is contained in the manufacturer’s literature contained in Chapter 5.

(4) Changing Engine Oil

Follow the instructions contained in the Chapter 5 engine manufacturer’s literature.

NOTE: Check the oil level a minimum of 10 minutes after the engine has stopped running to allow oil drainage from the upper engine in the crankcase. Add oil to the full mark on the dipstick. Inspect oil condition for evidence of incomplete combustion, coolant, or fuel contamination.

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(5) Changing the Engine Oil Filter

Follow the instructions contained in the Chapter 5 engine manufacturer’s literature.

CAUTION: IF OIL LEVEL IS CONSISTENTLY ABOVE NORMAL AND EXCESS LUBRICATING OIL HAS NOT BEEN ADDED TO THE CRANKCASE, CONTACT AN AUTHORIZED SERVICE OUTLET FOR INSTRUCTIONS. SERIOUS ENGINE DAMAGE MAY RESULT FROM FUEL OR COOLANT DILUTION OF ENGINE LUBRICATING OIL. NEVER FILL THE CRANKCASE ABOVE THE FULL MARK ON THE DIPSTICK. OVERFILLING COULD CAUSE SERIOUS ENGINE DAMAGE. NEVER RELY SOLELY ON THE STATED CAPACITY. FILL THE CRANKCASE TO THE FULL MARK ON THE DIPSTICK. MIXING LUBRICANTS OF DIFFERENT VISCOSITIES OR CHEMICAL PROPERTIES WILL DEGRADE THE ORIGINAL LUBRICANT.

NOTE: The use of high sulfur (above 0.5% mass) will require shorter oil and filter change intervals. Refer to the engine manufacturer’s instructions.

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(6) Air Filter

The air filter assembly includes a washable, dry type element, dust collection valve, and filter restriction indicator. A definite schedule for filter element replacement cannot be specified due to variable operating conditions. The filter should be cleaned or replace whenever the maximum allowable air filter restriction has been reached or annually, whichever occurs first. The service indicator incorporates an integral spring-biased gauge designed to unload at the fixed setting of the device. When the service indicator unloads, a red gauge is visible through a window in the indicator body, indicating that the filter should be cleaned or replaced. The indicator gauge may be reset by pushing in the rubber diaphragm on the end of the device.

NOTE: The service indicator does not measure filter efficiency. It measures pressure drop across the filter for the purpose of determining whether the filter is operating within its design range. Filter efficiency is a measure of the filter’s ability to remove particulate matter from the air stream. (a) Filter Replacement

(1) Remove all exterior dust and foreign matter from the air

cleaner housing with a damp cloth. (2) Press the rubber cup to empty the dust collection valve. (3) Twist the filter housing cap to unlock the cap from the housing.

Remove cap, and the carefully remove filter element as to not disturb the accumulated dust on it.

(4) Clean and dry the inside of the filter hood, cap, and base with

a damp lint free cloth. (5) Gently pat the sides of the cover and element to loosen dirt.

Check the condition of all gaskets and seals. (b) Filter Cleaning

Do not clean the filter element; it is a serviced as a disposable element, replace when clogged. Pro

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(7) Cooling System Coolant Level Servicing

CAUTION: ON UNITS EQUIPPED WITH OPTIONAL HOT WATER HEATING SYSTEM, THE WATER SHUT OFF SOLENOID MUST BE ENERGIZED (OPEN) TO ALLOW FILLING THE ENGINE COOLANT HEAT EXCHANGER AND PURGING AIR FROM THE SYSTEM.

NOTE: Unless a malfunction in the engine cooling system exists, the engine coolant level should be checked with the engine cold. The cooling system should be initially filled through the radiator filler neck located at the top of the generator set enclosure on the right side of the unit. Replace the radiator pressure cap after the cooling system has been filled and purged of air.

CAUTION: NEVER REMOVE THE CAP FROM A HOT, PRESSURIZED RADIATOR. THE SUDDEN RELEASE OF PRESSURE MAY RESULT IN LOSS OF COOLANT AND POSSIBLE PERSONAL INJURY. (a) With the engine off and cold, remove the pressure cap from the

expansion tank filler neck. Fill the cooling system through the filler neck on the radiator.

(b) Start the engine and allow it to run at no-load speed to circulate the

coolant and eliminate trapped air from the system. Continue adding coolant to the expansion tank until coolant level is ¾-inch below the top of the filler neck. Then reinstall the pressure cap.

NOTE: Cooling system capacity is 5.5 gallons (21 liters). An all season ethylene glycol antifreeze is recommended for use in the cooling system. It must meet the general requirements for engine coolant described in SAE Information Report No. J814 and SAE Recommended Practice No. J1941. Further information on coolant requirements may be found in the engine manufacturer’s literature contained in Chapter 5.

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CAUTION: DO NOT USE METHYL ALCOHOL BASE OR METHOXY PROPANOL ANTIFREEZE. DO NOT USE COOLANT CONCENTRATE CONTAINING SEALANT OR STOP LEAK ADDITIVES. DO NOT USE COOLANT CONCENTRATE CONTAINING MORE THAN 0.1% ANHYDROUS METASILICATE. THIS TYPE OF COOLANT ADDITIVE IS INTENDED FOR ALUMINUM ENGINES AND MAY CAUSE COOLANT TO GEL, FORMING A DEPOSIT THAT REDUCES HEAT TRANSFER AND COOLANT FLOW. OBSERVE THE FOLLOWING PRECAUTIONS WHEN SERVICING THE ENGINE COOLANT SYSTEM: • NEVER ADD COLD LIQUID TO A HOT ENGINE. IT MAY

CRACK THE CYLINDER HEAD OR BLOCK. • NEVER OPERATE THE ENGINE WITHOUT COOLANT. • NEVER USE A COOLING SYSTEM SEALANT. • USE A SOLUTION OF 50% ALL-SEASON ETHYLENE

GLYCOL BASE ANTIFREEZE AND 50% CLEAN, DEIONIZED OR DISTILLED WATER MIXTURE.

(8) Engine Cooling System Drain, Flush, and Refill

(a) Position a suitable capacity container to collect engine coolant under

the drain valve located at the bottom of the radiator. Open the drain valve. Remove the pressure cap from the radiator to facilitate drainage.

NOTE: Engine cooling system capacity is 5.5 gallons (21 liters). (b) Allow the engine to cool then close the drain valve and fill the engine

cooling system with clean, soft water. (c) Start the engine and allow the soft water to circulate through the

cooling system for 15 minutes then drain the cooling system completely.

(d) Refill the cooling system with antifreeze solution following the

instructions provided in Paragraph D.1.

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B- FUEL SYSTEM

(1) Fuel Tank Servicing

(a) Fill the tank with fresh, clean low sulfur diesel fuel conforming to the engine manufacturer’s recommendations.

NOTE: Use Grade No. 2-D diesel fuel meeting the requirements of ASTM designation D975. The use of low sulfur fuel containing a maximum 0.5 mass percent sulfur is recommended to reduce engine wear, formation of excessive deposits, and reduce exhaust pollutants. Supplement fuel additive are not recommended due to potential injector system or engine damage. A biocide additive may be used as a temporary treatment for control of microbial growth in stored fuel.

WARNING: ALWAYS STOP THE ENGINE BEFORE REFUELING, CLEAN THE FILLER CAP TO AVOID THE INTRODUCTION OF CONTAMINANTS DURING REFUELING, DIESEL FUEL IS A FLAMMABLE LIQUID, NEVER EXPOSE FUEL TO OPEN FLAME, SMOKING MATERIAL, OR SPARKS. OPEN THE TANK SLOWLY TO AVOID FUEL VAPOR SPRAY.

NOTE: Fuel tank capacity is 78 U.S. gallons (264.95 liters). It is good practice to fill the fuel tank at the end of the day since incoming fuel will evacuate the moisture-laden air and prevent condensation overnight. To assure satisfactory performance and starting capability, the fuel cetane number should not be lower than 40. The cetane number indicates the ignition quality of a diesel fuel. Ignition quality is that property of the fuel that causes diesel engine auto-ignition. Pro

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(2) Fuel Tank Drainage (a) Loosen the plug at the bottom of the fuel tank every 500 hours to

drain off collected sediment and moisture. (b) Drain the tank contents fully, rinse, and replenish with fresh, clean

fuel in the event that fuel contaminated by microbial growth or excessive water content is introduced into the tank.

WARNING: DRAIN DIESEL FUEL ONLY IN A WELL-VENTILATED AREA AWAY FROM EXPOSURE TO OPEN FLAME, SPARKS, OR HOT SURFACES. ALWAYS USE AN APPROVED CONTAINER. AVOID FUEL CONTACT WITH SKIN OR PROLONGED BREATHING OF VAPORS. (c) Provide a suitable capacity container for the residual fuel remaining

in the tank. (d) To drain the tank, remove tank drain plug.

NOTE: Open the fill cap on the top of the tank to facilitate tank drainage. (e) Allow the tank to empty into the container provided. Replace tank

drain plug.

C- DRIVE BELT A single multi v-ribbed belt drives the alternator and fan. The engine is equipped with an automotive drive belt tensioner. The alternator/fan belt, for proper charging and cooling system operation, should be in good condition and at the proper tension at all times. Since drive belts are frictional, the ability of belts to transmit power depends upon proper tension, the degree of contact between the belts and pulleys, and drive speed.

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D- BATTERY SERVICING

A single 12 volt sealed lead-acid battery provides 12 VDC operating power to the engine, and runs part of the unit electrical system, the clearance lights, and panel lights. The battery, which conforms to BCI Group No. 31, provides 1100 CCA starting current and 200 minutes reserve capacity.

WARNING: BATTERY GAS IS EXPLOSIVE. NEVER EXPOSE BATTERIES TO OPEN FLAME, SPARKS, OR SMOKING MATERIALS, NEVER CHECK BATTERY CHARGE BY SHORTING THE NEGATIVE AND POSITIVE BATTERY POSTS. ALWAYS CHECK BATTERY CHARGE USING A VOLTMETER OR DISCHARGE TESTER. ALWAYS REMOVE ADEQUATE VENTILATION WHEN WORKING NEAR BATTERIES. ALWAYS LIFT PLASTIC CASE BATTERIES WITH A BATTERY CARRIER. COMPRESSION OF THE SIDES MAY CAUSE ACID TO SPEW FROM THE VENT HOLES. BATTERIES CONTAIN SULFURIC ACID. AVOID CONTACT WITH SKIN, EYES, AND CLOTHING. WEAR SAFETY GLASSES, OR PREFERABLY, A FULL FACE SHIELD AND RUBBER GLOVES WHEN HANDLING BATTERIES. IN CASE OF ACID CONTACT WITH SKIN OR EYES, FLUSH THE AREA IMMEDIATELY WITH WATER FOR A MINIMUM OF 15 MINUTES AND GET PROMPT MEDICAL TREATMENT. USE BAKING SODA TO NEUTRALIZE ACID SPILLED ON SKIN. IF ACID IS INGESTED, DRINK LARGE AMOUNTS OF WATER OR MILK FOLLOWED BY MILK OF MAGNESIA, BEATEN EGGS OR VEGETABLE OIL. (1) Periodic Maintenance

(a) Open the unit door to the left of the unit control panel. Turn the unit battery switch to the “O” off position.

(b) Examine the battery for evidence of physical damage, leakage, loose

(or excessively tight) or corroded terminal clamps.

NOTE: Evidence of the above conditions may indicate poor battery condition. Refer to Chapter 3, Section 2, for further testing. If the battery passes the specific gravity test, open circuit voltage, and high rate discharge test, the battery may be recharged to full capacity. Perform a battery drain test to check for current drain when the ignition switch is turned off.

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(c) Clean the cable clamps and battery terminal posts with a wire brush/battery terminal cleaner. Neutralize corrosive build up with a solution of baking soda and water (one part baking soda and four parts water). Coat the terminals with petroleum jelly or commercial corrosion inhibitor. Remove the battery and clean the battery tray with the same baking soda and water solution. Rinse thoroughly. If corrosion is present sand and recoat area with a cold galvanization compound, or zinc rich primer and paint if cold galvanization is not available.

(d) Reinstall the battery in the tray and reconnect the cable clamps to

the terminals. Install the positive (+) cable clamp on the battery (+) terminal post; then install the negative (-) cable clamp on the battery (-) terminal post. Tighten the terminal clamps securely. DO NOT OVER TIGHTEN. Apply a corrosion inhibitor to the terminal clamps.

(e) Inspect the battery hold down clamps. Ensure they hold the battery

securely in place by keeping them clean, corrosion free and tightly clamped to the unit frame. Do not tighten to the point of cracking the battery! If excessively corroded, damaged, or unable to keep battery secure, replace the hold down clamps and frame.

NOTE: The need for battery service can be reduced and battery lift span can be extended by keeping the battery clean and dry. Accumulated dirt and moisture permit slow battery discharge between the terminals.

CAUTION: TO AVOID DAMAGE TO CABLE CLAMPS, ALWAYS USE A BATTERY CLAMP PULLER TO REMOVE CLAMPS FROM TERMINAL POSTS AND A CLAMP SPREADER ON REINSTALLATION. WHENEVER BATTERY REPLACEMENT IS REQUIRED, ENSURE THAT THE USED LEAD-ACID BATTERY IS DISPOSED OF AT AN AUTHORIZED RECYCLING CENTER.

(2) Charging a Discharged Battery

CAUTION: IF THE BATTERY FEELS HOT (125°F) (52°C) OR IF VIOLENT GASSING OR SPEWING OF ELECTROLYTE THROUGH THE VENT HOLES OCCURS, PAUSE CHARGING UNTIL BATTERY COOLS AND REDUCE THE CHARGING RATE. (a) Before charging a battery, measure the open circuit voltage using

any DC voltmeter. If below 11.5 VDC, allow battery to rest for 24 hours with no load, either by turning off the battery switch if the battery is still in the unit, or disconnecting the unit battery cable from

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the battery. If the battery is still below 11.5 VDC after a resting period, consider it deeply discharged, and possibly damaged from being discharged. ALWAYS Load test any battery that is charged from this condition to ensure no damage has occurred to the battery.

(b) If the battery is equipped with removable cell caps, remove and

inspect the water level. If below the top of the plates, the battery has experienced sulfating and will require longer to charge. Fill battery cell with distilled or deionized water to the bottom of the fill port.

(c) Make sure that all charger connections are clean and tight. Follow

charger manufacturer’s instructions on how to connect the battery charger.

(d) If battery is still in the unit, turn the unit battery switch to “O” off. (e) If applicable, set battery charger to 12VDC, maximum charge rate of

30 amps or less. A slower charge rate will extend the life of the battery and reduce the chance of creating dead cells and other battery damage while charging it.

(f) Turn on battery charger, verify ammeter deflection occurs and the

charge rate is at least ½ of set point on charger within 1 minute of the start of charging.

(g) If the charge rate is very low and the battery is completely

discharged (below 11.5 Volts after a 24 hour rest), it is normal, the battery acid has diluted to the point of no longer being conductive. Set the battery charger to the highest charge rate possible for 12Volts. Turn down current rate to below 30 amps once the charge rate increases. If the battery does not begin accepting charge at a higher rate after 2 hours, replace battery as it is permanently damaged.

(h) Continue charging battery until specific gravity is greater than 1.26 if

a hydrometer is available, free gassing occurs from the cells if the cell caps are removable, until the charge rate falls to less than ½ the highest rate seen, or the automatic battery charger terminates the charge.

(i) Load test the battery using a 3 minute battery test method.

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NOTE: Time required to charge a battery will vary depending upon the following factors: • Size of Battery. A completely discharged large, heavy-duty

fleet battery requires more than twice the charging time than does a completely discharged small passenger car battery.

• Temperature. A longer time will be required to charge any battery at 0°F than at 80°F. When a fast charger is connected to a cold battery, the current accepted by the battery will be very slow at first, then in time, the battery will accept a higher rate as the battery warms.

• Charger Capacity. A charger that can supply only five amperes will require a much longer period of charging time than a charger that can supply 30 amperes of current.

• State-of Charge. A completely discharged battery requires more than twice as much charge time as one half-charged. Since the electrolyte is nearly pure water and a poor conductor in a completely discharged battery, the current accepted by the battery is very low at first. Later as the charging current causes the electrolyte acid content to increase, the charging current will increase.

E- DELIVERED AIR SYSTEM

(1) Air Inlet Filter

NOTE: On air conditioning units, the blower inlet filter is an expanded steel, corrugated mesh assembly installed in the blower inlet housing. Remove the sheet metal screws securing the filter element retainer and remove the filter element. On units with optional coolant heat exchanger, a foam filter is used. The filter is accessible through a door on the right side of the unit, opposite the electrical box. To ensure proper unit operation under various ambient conditions, perform a visual inspection of filter condition as a regular part of every preventive maintenance procedure. To ensure optimum unit performance, clean the filter element whenever contamination is observed and replace a damaged filter immediately.

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(a) Cleaning the Filter

(1) Remove the filter panel from the blower inlet. (2) Tap the sides of the element gently to dislodge accumulated

dirt.

WARNING: REDUCE AIR PRESSURE TO 30 PSI WHEN USED FOR CLEANING PURPOSES. WEAR EYE PROTECTION. (3) Remove loosened particles with filtered compressed air.

(b) Washing the Element

(1) If the element is coated with oily fill, or soot, wash in a solution of hot water and detergent. Let the element soak for 10-15 minutes. Agitate periodically.

(2) Rinse the element in clear water. (3) Allow the element to dry thoroughly before reinstallation.

CAUTION: NEVER WASH THE ELEMENT IN ANY SOLVENT. (4) Replace a damaged element. (5) Reinstall the filter in the blower inlet adapter.

(2) Blower Motor

WARNING: MAINTENANCE SHOULD ONLY BE PERFORMED BY TRAINED PERSONNEL WHO ARE AWARE OF THE HAZARDS ASSOCIATED WITH ROTATING EQUIPMENT. NEVER ATTEMPT MAINTENANCE ON ANY FAN DRIVE UNLESS THE POWER SUPPLY HAS BEEN LOCKED OUT AND TAGGED AND THE BLOWER MOTOR HAS BEEN LOCKED OUT AND TAGGED AND THE IMPELLER SECURED. DISCONNECT ALL POWER SOURCES TO THE UNIT AND DISCHARGE ALL COMPONENTS THAT MAY RETAIN AN ELECTRICAL CHARGE BEFORE ATTEMPTING MAINTENANCE OR REPAIR. FAILURE TO OBSERVE THIS WARNING MAY RESULT IN PERSONAL INJURY.

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Blower maintenance consists primarily of periodic inspection, cleaning, and lubrication. Changes in operating characteristics may indicate the need for maintenance. Sudden changes may indicate severe problems or dangerous conditions that are developing. Operational vibration levels are one of the best indicators of blower condition. Careful observation and monitoring of vibration levels can reveal problems in the early stages of development. Changes in speed may indicate maintenance is required. If any unusual noises are detected, their cause should be determined and corrective action taken. High motor temperatures may indicate that cooling airflow is blocked or that input amperage has increased. High bearing temperatures may indicate a need for lubrication. Any of these conditions may result in poor blower performance. (a) Re-Lubrication

NOTE: Motors are factory lubricated and do not require initial lubrication.

CAUTION: EXCESSIVE OR TOO FREQUENT LUBRICATION MAY DAMAGE THE MOTOR AS SEVERELY AS INADEQUATE LUBRICATION. (1) The motor should be lubricated at the grease fittings provided

every six months.

CAUTION: GREASE OF DIFFERENT BASES MAY NOT BE COMPATIBLE WHEN MIXED, USE ONLY SRI #2 LUBRICANT. MIXING INCOMPATIBLE LUBRICANTS CAN RESULT IN REDUCED BEARING LIFE AND PREMATURE BEARING FAILURE. (2) Re-lubricate with Chevron SRI #2 grease while the motor is

still warm from operation, with the shaft stationary to facilitate purging old grease.

(3) Clean the area surrounding the grease fittings and purge

plugs. Remove the purge plugs opposite the grease fittings to permit the purging of the old grease.

(4) Remove hardened grease from the drain ports with a stiff wire

or rod. (5) Add grease to the inlet grease fittings with a handgun until a

small amount of fresh grease is forced out the drain ports.

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(6) Remove excess grease from the ports and run the motor for one-half hour to allow purging of excess grease. Reinstall plugs.

F- REFRIGERATION SYSTEM

(1) Cleaning the Condenser Coil

Insufficient airflow through the outside condenser coil will result in inefficient heat transfer, producing poor condensing action and excessively high discharge pressure. Refrigerant vapor is introduced into the upper two-thirds of the condenser coil through a distributor tube. Heat is removed from the hot refrigerant vapor in the upper section of the condenser. Condensed refrigerant fills the lower third of the coil with liquid. Excessively high condensing pressure will allow superheated vapor to enter the liquid line and the expansion orifices. Optimum condenser performance requires unrestricted airflow through the condenser coil. Insufficient airflow may result from a dirty coil or from a defective or inoperative condenser fan. Insufficient airflow may result from a slow or non-turning propeller fan or from a dirty coil. Propeller fan speed may be checked with an accurate stroboscope tachometer. A visual inspection will reveal a dirty coil. If the problem is determined to be a dirty coil, follow the instructions provided below for cleaning the coil. Refer to “Troubleshooting,” Chapter 2, Section 2, for determining the cause for poor condenser coil performance. (a) The condenser (outside coil) should be cleaned at 30-day intervals. (b) Remove the coil guard screens. (c) Clean the coil surface with a soft bristle brush using a stroke in line

with the fins.

CAUTION: TO AVOID FIN COMPRESSION, DO NOT BRUSH HORIZONTALLY ACROSS THE COIL SURFACE. CLEANING SOLVENTS MUST NOT BE USED SINCE THEY LEAVE AN OILY FILM THAT REDUCES HEAT TRANSFER. LARGE BLOCKAGES, DIRT, AND GREASE DEPOSITS MUST BE PHYSICALLY REMOVED. BENT FINS SHOULD BE CAREFULLY STRAIGHTENED. (d) Reinstall the coil guard screens.

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(2) Cleaning the Evaporator Coil

NOTE: Condensed moisture collects dust and lint on the air inlet side of the coil. The evaporator coil should require cleaning only if the unit has been operated with a defective or missing inlet filter. (a) The evaporator coil should be inspected annually and cleaned if

required. (b) Remove the rear panel for coil access. (c) Remove the coilbox cover, exposing the evaporator coil. (d) Clean the coil surface with a soft bristle brush using an upward

stroke in line with the fins.

CAUTION: TO AVOID FIN COMPRESSION, DO NOT BRUSH HORIZONTALLY ACROSS THE COIL SURFACE. CLEANING SOLVENTS MUST NOT BE USED SINCE THEY LEAVE AN OILY FILM THAT REDUCES HEAT TRANSFER. LARGE BLOCKAGES, DIRT, AND GREASE DEPOSITS MUST BE PHYSICALLY REMOVED. BENT FINS SHOULD BE CAREFULLY STRAIGHTENED. (e) Clean the condensation tray and drain hole. (f) Replace the coilbox cover and rear sheet metal panel.

(3) Refrigerant Recovery

Refrigerant recovery is done to either service a refrigeration system problem or to remedy an overcharge condition. To recover refrigerant, perform the following:

CAUTION: PURGING OF THE REFRIGERANT SYSTEM TO ATMOSPHERE IS ILLEGAL AND VIOLATES FEDERAL EPA (ENVIRONMENTAL PROTECTION AGENCY) LAWS AND REGULATIONS. ALWAYS RECOVER AND RECYCLE REFRIGERANTS.

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WARNING: EXTREME CAUTION SHOULD BE USED WHEN WORKING WITH LIQUID REFRIGERANT. PROTECT EYES AND EXPOSED BODY PARTS FROM ACCIDENTAL REFRIGERANT SPRAY. SEVERE FROSTBITE OR EYE DAMAGE COULD OCCUR. IF FROSTBITE HAS OCCURRED OR IF IRRITATION PERSISTS, SEEK MEDICAL ATTENTION AS SOON AS POSSIBLE. IN CASE OF EYE CONTACT, IMMEDIATELY FLUSH THE EYES WITH RUNNING WATER FOR 15 MINUTES. (a) Connect the hoses from the manifold gauge set to the service valves

on the high and low side of the system. (b) Connect the discharge hose from the manifold set to a commercial

refrigerant recovery system or refrigerant recovery/recycling system. (c) Open both valves of the gauge set. Ensure that the vapor and liquid

valves on the refrigerant recovery/recycling tank are open. (d) Close the accumulator and oil drain valves. Ensure that the recycle

start switch is in the “OFF” position. (e) Turn on the recovery unit start switch. The unit will automatically

shut down when recovery is complete. Repeat this step if pressure rises above “0” psig.

(f) Drain the compressor oil into the oil receptacle bottle.

NOTE: When the system is recharged, the lost oil must be replaced. Measure the amount of oil removed during the recovery process and replenish the system with the same amount of new compressor oil before recharging. Verify compressor oil levels after the first run of a recharged unit.

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(4) Filter/Drier

The filter/drier (F1) removes moisture, solid particle contaminants, acid, sludge, and varnish from the liquid refrigerant. A desiccant block element is installed in the filter/drier shell that collects and holds a limited amount of moisture before becoming supersaturated. Excess moisture will circulate in the system. At lower ambient, the moisture will freeze in the evaporator, restricting refrigerant flow, reducing the cooling capacity of the evaporator; intermittent refrigeration system operation may be due to supersaturated desiccant in the filter/drier. A moisture indicating sight glass is installed immediately downstream from the filter. The sight glass element indicates the refrigerant moisture content by color change. Moisture is indicated by a pink color. If the system is dry, the element is a blue color. A pink color indicates a saturated desiccant cartridge, and it should be replaced. A restricted filter element is indicated by a significant pressure drop between the filter inlet and outlet. Pressure drop across the filter may be checked at access port (P7) and (P8). The filter should be cleaned when pressure drop exceeds 3 psi.

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25…Shut Off Valve (V4) 28…Service Port (P5)

26…Check Valve (V7) 29…Filter Drier Cover Plate

27…Service Valve (V6) 30…Filter Drier Shell

REFRIGERANT FILTER/DRIER

FIGURE 5

25

26

2728

29

30

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NOTE: Excessive moisture may be removed from the system by installing temporary clean-up cartridges and operating the system to collect the contaminants. Replace the filter cartridge until all contaminants has been removed from the system. To clean the system after a motor burnout, install acid removal cores. Change the elements until the acid level drops below 0.05 mg KOH. Use a standard acid test kit to check oil ph level.

CAUTION: TO AVOID VENTING REFRIGERANT TO ATMOSPHERE, ALL PRESSURE MUST BE REMOVED FROM THE FILTER/DRIER BEFORE ATTEMPTING TO SERVICE THE CARTRIDGE. (a) To isolate the filter/drier from the system, close the shut off valve

(V4). The check valve (V7) installed downstream from the filter/drier prevents reverse flow of refrigerant.

CAUTION: ALWAYS USE APPROVED REFRIGERANT RECLAMATION METHODS WHEN RECOVERING REFRIGERATION SYSTEM PRESSURE. PURGING OF THE REFRIGERATION SYSTEM TO ATMOSPHERE IS ILLEGAL AND VIOLATES FEDERAL EPA (ENVIRONMENTAL PROTECTION AGENCY) LAWS AND REGULATIONS. ALWAYS RECOVER AND RECYCLE REFRIGERANTS. (b) Close service valve (V6) and install recovery equipment suction hose

at service port (P5). Connect recovery equipment outlet to service port (P1) at service valve (V11) located on compressor discharge plumbing. Open the angle valves (V6) and (V11) and recover refrigerant from the isolated section into the unit refrigeration system. When all pressure has been removed from the isolated section or the recovery equipment automatically turns off, close the angle valves (V6) and (V11) and disconnect the recovery equipment. Only after all refrigerant is removed from the isolated section can the fasteners securing the filter housing cover may be removed.

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WARNING: EXERCISE CAUTION WHEN DISASSEMBLING ANY SPRING-LOADED DEVICE, BREAKING CONNECTIONS, OR OPENING PORTS. RESIDUAL PRESSURE MAY BE PRESENT, AFTER ISOLATION OR PUMP DOWN PROCEDURES HAVE BEEN ACCOMPLISHED; ALWAYS WORK SLOWLY AND CAREFULLY WHEN BREAKING CONNECTIONS OR OPENING PORTS. WEAR PROTECTIVE CLOTHING, LINED BUTYL GLOVES, EYE PROTECTION, AND FULL FACE GUARD WHEN SERVICING THE REFRIGERANT FILTER/DRIER. IN CASE OF SKIN OR EYE CONTACT WITH LIQUID REFRIGERANT, TREAT THE AFFECTED AREAS IMMEDIATELY FOR FROSTBITE AND SEEK MEDICAL ATTENTION AS SOON AS POSSIBLE. EXERCISE CAUTION WHEN DISASSEMBLING ANY SPRING-LOADED DEVICE, BREAKING CONNECTIONS, OR OPENING PORTS. RESIDUAL PRESSURE MAY BE PRESENT, AFTER ISOLATION OR PUMP DOWN PROCEDURES HAVE BEEN ACCOMPLISHED; ALWAYS WORK SLOWLY AND CAREFULLY WHEN BREAKING CONNECTIONS OR OPENING PORTS. WEAR PROTECTIVE CLOTHING, LINED BUTYL GLOVES, EYE PROTECTION, AND FULL FACE GUARD WHEN SERVICING THE REFRIGERANT FILTER/DRIER. IN CASE OF SKIN OR EYE CONTACT WITH LIQUID REFRIGERANT, TREAT THE AFFECTED AREAS IMMEDIATELY FOR FROSTBITE AND SEEK MEDICAL ATTENTION AS SOON AS POSSIBLE. (c) Slowly and evenly loosen the fasteners securing the filter cover

plate. Depress the cover plate by hand and remove the fasteners. Slowly relieve spring pressure against the cover plate and remove the plate gasket and compression spring.

(d) Remove the desiccant block from the filter shell. Discard the

saturated desiccant block element.

CAUTION: REMOVE ACTIVE DESICCANT FROM THE SEALED STORAGE CONTAINER ONLY WHEN READY TO INSTALL. EXPOSURE OF THE CARTRIDGE TO THE ATMOSPHERE WILL RESULT IN MOISTURE CONTAMINATION. (e) Clean the filter/drier shell and all parts. (f) Reassemble the filter/drier using a fresh desiccant block element and

new gaskets.

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(g) Using the refrigerant recovery device, or a high vacuum pump, pull a deep vacuum in the isolated section to remove all air and contaminates introduced during the servicing operation using service valve (V6) and access port (P5). If using a refrigerant recovery device, be sure to vent the pump output to atmosphere to avoid contaminating stored refrigerant. Close service valve (V6) before disconnecting the equipment.

(h) Replace cap on service port (P5) and ensure service valve (V6) is

closed. Open shutoff valve (V4). (i) Start unit in cooling mode and check filter drier cover gasket for any

leaks.

(5) Compressor Oil Servicing

Addition of oil should be necessary only under the following conditions: when a leak develops, after compressor replacement, or after system overhaul. The compressor does not consume oil. Oil level in the compressor can only be evaluated when the compressor is shut off Observe the oil level in the sight glass on the front of the compressor. Add oil only if the oil level is below the bottom of the sight glass. If the oil level is above the sight glass, before removing oil, it must be determined whether it is due to refrigerant in the compressor oil sump or an overcharge of oil.

NOTE: During operation, the oil level will vary due to load conditions of the system, superheat, and position in the circuit. Since compressor oil is highly miscible with refrigerant, oil level is actually the level of the refrigerant – oil mixture. Refer to the manufacturer’s service literature contained in Chapter 5 for the recommended compressor oil charge.

CAUTION: OIL OVERCHARGING CAUSES EXCESSIVE OIL CIRCULATION AND POSSIBLE OIL ENTRAPMENT IN THE SYSTEM UNDER CERTAIN LOAD AND OPERATING CONDITIONS. OIL UNDERCHARGING WILL RESULT IN POOR LUBRICATION AND EVENTUALLY LEAD TO BEARING FAILURE DUE TO LACK OF LUBRICATION. INSTALL ONLY TLD PART NO. 1053583 COMPRESSOR OIL, EXPOSING THE REFRIGERATION SYSTEM TO THE WRONG TYPE OF REFRIGERATION OIL WILL RENDER THE SYSTEM UNUSABLE.

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Add oil through the charging valve adjacent to the sight glass. Drain oil from the compressor oil drain valves (V14, V15).

(6) Condenser Fan Motor

WARNING: MAINTENANCE SHOULD ONLY BE PERFORMED BY TRAINED PERSONNEL WHO ARE AWARE OF THE HAZARDS ASSOCIATED WITH ROTATING EQUIPMENT. NEVER ATTEMPT MAINTENANCE ON ANY FAN DRIVE UNLESS THE POWER SUPPLY HAS BEEN LOCKED OUT AND TAGGED AND THE PROPELLER HAS BEEN SECURED. DISCONNECT ALL POWER SOURCES TO THE UNIT AND DISCHARGE ALL COMPONENTS WHICH MAY RETAIN AN ELECTRICAL CHARGE BEFORE ATTEMPTING MAINTENANCE OR REPAIR. FAILURE TO OBSERVE THIS WARNING MAY RESULT IN PERSONAL INJURY. Fan maintenance consists primarily of periodic inspection, cleaning, and re-lubrication. Changes in operating characteristics may indicate the need for maintenance. Sudden changes may indicate severe problems or dangerous conditions that are developing. Operational vibration levels are one of the best indicators of fan conditional. Careful observation and monitoring of vibration levels can reveal problems in the early stages of development. Changes in speed may indicate maintenance is required. If any unusual noises are detected, their cause should be determined and corrective action taken. High motor temperatures may indicate that cooling airflow is blocked or that input amperage has increased. High bearing temperatures may indicate improper lubrication. Any of these conditions may result in poor fan performance. (a) Re-Lubrication

NOTE: Motors are factory lubricated and do not require initial lubrication.

CAUTION: EXCESSIVE OR TOO FREQUENT LUBRICATION MAY DAMAGE THE MOTOR AS SEVERELY AS INADEQUATE LUBRICATION. (1) The motor should be lubricated at the grease fittings provided

at the intervals recommended below (see Table 1).

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Bearing No. Location Qty. Lubricant

Lubrication Interval *

6309-2ZJC3 Shaft end 0.4 oz. Annually 6209-2ZJC3 Opposite end 0.2 oz. 18 months

Table 1- Condenser Fan Motor Lubrication

(2) Re-lubricate with Chevron SRI #2 grease while the motor is

still warm from operation. Re-Lubricate with the shaft stationary to facilitate purging the old grease.

(3) Clean the area surrounding the grease fittings and purge

plugs. Remove the purge plugs opposite the grease fittings to permit purging old grease.

(4) Remove hardened grease from the drain ports with a stiff wire

or rod. (5) Add the recommended amount of grease to the inlet grease

fittings with a handgun. (6) Remove excess grease from the ports and run the motor for

one-half hour before replacing the plugs to allow purging of excess grease.

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(7) Evacuating the Refrigeration System

High compressor discharge pressure may indicate the presence of non-condensable gases in the system. The presence of contaminants may be verified by the following procedure. The degree of contamination may be determined by gas chromatography utilizing a sample of vaporized refrigerant liquid.

NOTE: Refrigerant is hygroscopic and will absorb moisture readily, forming corrosive acids through hydrolysis. The greater the moisture content, the more concentrated the acid. The corrosive action of the acid releases contaminants into the refrigeration system which degrade the heat transfer capability of the refrigerant and erode circuit piping, producing pin hole leaks. The most effective means of evacuating excessive moisture from the system is with the use of a vacuum pump. Vacuum releases pressure from condensed moisture in the system, changing the liquid to a vapor that can be easily removed by the vacuum pump. Icing of the expansion control orifices will restrict refrigerant flow through the evaporator and prevent the unit from cooling to its full capabilities. (a) Determining the Degree of Contamination Procedure

(1) Allow the refrigeration system to remain inoperative for a minimum of 6 hours (overnight is preferred).

(2) Measure and record the ambient temperature. (3) Connect a compound pressure gauge to the service access

valve located on the high pressure side of the system. (4) Note and record the pressure indicated by the gauge. (5) Determine from the “Temperature – Pressure Relation” table

for HFC-134a contained in Chapter 5 the refrigerant saturation temperature corresponding to the pressure obtained above. If the saturation temperature is the same as the ambient temperature, the refrigeration system is not contaminated. If saturation temperature is above ambient temperature, non-condensable gases are present in the system; and remove moisture from the refrigerant. Evacuation is the most effective method for removing moisture and non-condensable gases after the system has been opened for repairs or maintenance procedures.

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(b) Evacuating the Entire System

Required Equipment:

• Vacuum pump (cat. No. 33008) with hose (cat. No. 59389), adapters, and fittings.

• Refrigeration charging kit (cat. No. 40112).

• Approximately 50 lbs. of refrigerant.

NOTE: Complete system evacuation may be accomplished by using the ACE general refrigeration service cart. (1) First recover and recycle the complete refrigerant charge

removed from the system using a commercial recovery/recycling system approved for HFC-134a. The system must be able to separate lubricant from the recovered refrigerant and accurately indicate the amount of lubricant removed; automatically reclaim non-condensable gases; and remove moisture from the refrigerant. Operate the system in accordance with the manufacturer’s instructions.

NOTE: Refer to the flow diagram contained in Chapter 2, Section 2, for the location of specific refrigerant system components. Recover all pressure from the refrigeration system.

WARNING: USE CAUTION WHEN RECOVERING REFRIGERANT FROM THE SYSTEM OR INJURY TO PERSONNEL MAY RESULT.

CAUTION: RECOVERY CYLINDERS AND REFRIGERATION EQUIPMENT MUST BE EVACUATED AT THE START OF FILLING AND MUST NEVER BE FILLED WHILE UNDER POSITIVE AIR PRESSURE. FINAL PRESSURES SHOULD NOT EXCEED 300 PSIG (2,170 KpA). VACUUM PUMP DISCHARGE LINES SHOULD BE FREE OF RESTRICTIONS THAT COULD INCREASE DISCHARGE PRESSURE ABOVE 15 PSIG (205 kPa) AND RESULT IN THE FORMATION OF COMBUSTIBLE MIXTURES.

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WARNING: IF THE INITIAL AIR PRESSURE IS GREATER THAN ONE ATMOSPHERE, COMBUSTIBLE MIXTURES MAY FORM AS THE TANK IS FILLED. (2) Connect the hoses from the manifold gauge set to the service

valves on the high and low side of the system. (3) Connect the center hose from the manifold gauge set to the

vacuum pump connector. (4) Open the high and low side gauge manifold hand valves. (5) Operate the vacuum pump following the manufacturer’s

placarded instructions.

NOTE: The evacuation process can take several hours depending on the amount of moisture in the refrigeration system. (6) Observe the compound gauge on the low side of the system.

When the system has pumped down into a vacuum and the reading remains constant, allow the vacuum pump to continue running for an additional hour to ensure full removal of moisture; turn off pump and close valves.

NOTE: Should absolute pressure begin to rise, indicating a loss of vacuum, there may be foreign fluids in the system which must be boiled off, or there may be a system leak. (7) If the system is holding vacuum, charge the refrigeration

system as described in paragraph.

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(8) Charging the Refrigeration System

CAUTION: THE SYSTEM SHOULD BE CHARGED WITH REFRIGERANT ONLY AFTER IT HAS BEEN LEAK TESTED AND EVACUATED. DO NOT OVERFILL. REFER TO THE MANUFACTURER’S TECHNICAL MANUAL AND UNIT NAMEPLATE FOR SYSTEM CAPACITY. OVERCHARGING THE REFRIGERATION SYSTEM MAY RESULT IN EXCESSIVE HEAD PRESSURE AND LIQUID SPILL OVER INTO THE COMPRESSOR.

NOTE: A charging station, utilizing a cylinder filled with the exact amount of refrigerant required by the system, is recommended.

WARNING: EXTREME CAUTION SHOULD BE USED WHEN WORKING WITH LIQUID REFRIGERANT. PROTECT EYES AND EXPOSED BODY PARTS FROM ACCIDENTAL REFRIGERANT SPRAY. SEVERE FROSTBITE OR EYE DAMAGE COULD OCCUR. (a) Connect a manifold gauge set to the suction and discharge lines as

test ports (P2) and (P1). Close the shut off valve (V4). (b) Connect an R-134a refrigerant cylinder to service port (P5) at angle

valve (V6), located on the cover of the filter/drier (F1) using a 3/8-inch charging hose. Open the liquid valve on the cylinder and bleed the air from the hose at the unit end.

(c) Record the weight of the refrigerant cylinder. (d) Open angle valve (V6) and allow liquid refrigerant to flow into the

evaporator. (e) Start the engine and allow temperatures and pressures to stabilize.

Select the “COOL” position on the mode select switch (S5). Press the start button (S3).

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CAUTION: THE COMPRESSORS WILL CYCLE OFF AS SUCTION PRESSURE DROPS BELOW THE HIGH-LOW PRESSURE SWITCH SETTING. SLIGHTLY OPENING THE SHUT-OFF VALVE (V4) MAY PREVENT OR REDUCE CYCLING. DO NOT ALLOW COMPRESSORS TO OVERHEAT WITH REPEATED STARTS. (f) Observe refrigerant flow in the sight glass and monitor cylinder

weight. Continue running the unit fully charged with refrigerant (approximately 50 lbs).

(g) Record the weight of the refrigerant cylinder after charging the unit. (h) Perform a complete operational test of the system. (i) The best way of gauging refrigerant charge is through the liquid

subcooling. This is the difference between the saturation temperature of the liquid at the pressure as it enters the filter drier, and the actual measured temperature at the same point. This value should be between five and ten degrees F.

(9) Adding Refrigerant to the System

NOTE: Do not base the refrigerant charge on the cooling cycle operating pressures. Add refrigerant based on comparison of stabilized system pressure with the “Temperature and Pressure Relation” tables for HFC-134a refrigerant contained in Chapter 5. If pressure is below that specified for the ambient temperature, add refrigerant. (1) Connect the hoses from the manifold gauge set to the service

valves on the high and low side of the system. (2) Connect the center hose to the refrigerant source and purge air

from the hose. (3) Operate the system until the refrigeration system temperatures and

pressures have stabilized. (4) Open the low side manifold hand valve. (5) Add the required amount of refrigerant vapor to the system to bring

liquid line temperature to 5°F below the saturation temperature of the pressure measured at P8.

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CAUTION: DO NOT EXCEED 40 PSI (2.8 BAR) PRESURE ON THE LOW SIDE GAUGE. THIS WILL ASSURE THAT ONLY REFRIGERANT VAPOR ENTERS THE COMPRESSOR.

NOTE: At ambient temperatures below 80°F (27°C), warm the refrigerant container to aid refrigerant vaporization.

WARNING: DO NOT EXCEED 125°F (52°C).

G- GENERATOR

The generator requires no scheduled service other than periodic cleaning. (1) Cleaning

When inspection determines cleaning is necessary, clean the generator as follows: Wipe the exterior of the generator and fan housing screens with a clean, lint-free cloth or nylon bristle brush. Remove stubborn accumulations of dirt with an approved detergent or solvent. Remove loosened deposits with a vacuum cleaner or filtered compressed air at a pressure between 25-30 psi.

WARNING: USE EXTREME CARE WHEN CLEANING WITH SOLVENTS OR OTHER FLAMMABLE LIQUIDS. USE VOLTILE CLEANERS ONLY IN WELL-VENTILATED AREAS, AWAY FROM OPEN FLAMES AND SPARKS.

(2) Lubrication

The generator is equipped with a permanently lubricated, sealed bearing. Periodic lubrication is not required.

NOTE: The bearing requires no adjustments. Refer to the manufacturer’s service manual contained in Chapter 5 for testing and repair procedures.

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(3) Adjustment

The generator requires no adjustment. Refer to the manufacturer’s service manual contained in Chapter 5 for testing and repair procedures.

H- TRAILER

(1) Wheel Bearing Lubrication and Adjustment The only periodic running gear maintenance dictated by normal usage other than wheel and tire inspection is annual cleaning and relubrication, and readjustment of the wheel and steering hub bearings. Tire rotation should be performed at the time of wheel bearing maintenance.

NOTE: Tires should be replaced whenever excessive tread wear is indicated. (a) Wheel Hub Disassembly

NOTE: UNIT GROSS WEIGHT: 7800 lbs

(1) Preferably; jack up the whole unit and place jack–stands under

all four corners of the unit. If only one end is lifted at a time, ensure both wheels in contact with the ground are chocked. Never jack the unit from the side to remove two wheels.

(2) Loosen the lug nuts.

CAUTION: DO NOT JACK ON DIAGONALLY OPPOSITE CORNERS, OR IN ANY MANNER WHICH WOULD DISTORT THE FRAME. DO NOT RAISE WITH A FORK LIFT. ENSURE THAT THE WHEELS ARE CHOCKED ON THE CART OPPOSITE THE JACKING POINTS TO PREVENT CART MOVEMENT. (3) Position the jack under the lift points and raise the unit until the

wheels can be freely rotated. (4) Install jack stand supports under the axle at the lift points. (5) Remove the wheel and tire assemblies. (6) Remove the grease cap, cotter pin, castle nut, and tongue

washer from the spindle.

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(7) Remove the outer bearing cone and roller. Pull the hub off the wheel spindle. Remove and discard the grease seal. Remove the inner bearing cone and roller from the hub. Remove all traces of existing lubricant from the bearings, hubs, and axle spindle with solvent. Dry the bearings thoroughly.

CAUTION: DO NOT SPIN THE BEARINGS DRY WITH COMPRESSED AIR.

(b) Inspection

(1) Inspect the cups for scratches, pits, or cracks. If the cups are worn or damaged, remove them with a punch.

(2) Inspect the bearings for a cracked cage, nicked rollers,

brinelling, or seizure.

NOTE: Replace excessively worn bearings and cups. Always install the cups and bearings in replacement sets. Immediate bearing damage may result if a new bearing is installed in a worn cup. Replace the grease seal whenever the hub is removed.

(c) Assembly

NOTE: Prior to repacking the wheel bearings, determine whether sodium or lithium based grease is to be used. Sodium based grease is not compatible with lithium based grease and should not be intermixed. Therefore, do not lubricate wheel bearings without first ascertaining the type of original wheel bearing lubricant. Use of incompatible bearing lubricants could result in premature lubricant breakdown. (1) Install the inner and outer bearing cups in the hub with

appropriate installation tools. Seat the cups fully. Pack the inside of the hub with wheel bearing grease. Fill the hub until the grease is flush with the inside diameter of both bearing cups. Pack the bearing cones and roller with wheel bearing grease. Use a commercial bearing packer for this operation. If a packer is not available, work as much lubricant as possible between the rollers and cage. Lubricate the cone surfaces with grease. Refer to Table 2 for lubricant specifications.

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(2) Place the inner bearing cone and roller in the inner cup and install the grease seal with the appropriate driving tool. Ensure that the seal is properly seated. Install the hub on the wheel spindle. Keep the hub centered on the spindle to prevent damage to the grease seal or the spindle threads.

(3) Install the outer bearing cone and roller and tongue washer on

the spindle; then install the castle nut finger tight. (d) Adjusting Wheel Bearings

(1) Install the wheel and tire assembly on the hub and finger tighten the wheel nuts.

(2) Wipe any excess grease from the end of the spindle. (3) While rotating the wheel, torque the castle nut to 14-17 ft. lbs.

To seat the bearings. (4) Back off the castle nut as required to align the first cotter pin

hole in the nut with the hole in the spindle. Install a new steel cotter pin.

CAUTION: ALWAYS INSTALL A NEW STEEL COTTER PIN WHEN SERVICING THE HUB. (5) Check wheel hub alignment. If the wheel rotates freely with no

noticeable end play, install the grease cap. Readjust the hub if necessary.

(6) Torque the wheel lug nuts. Elevate the unit, remove the

maintenance stands, and lower the unit. (2) Wheels and Tires

NOTE: To ensure that tires wear evenly, resulting in longer tire life span and in efficient trailer performance, maintain the recommended tire inflation pressure and rotate the tire and wheel assemblies every 1200 hours of unit operation or every two years. Ensure that the valve caps are installed on valve stems to keep out water and dust contamination. Check tire pressure weekly and ensure that tires are filled to the air pressure marked on the trailer frame as stated below.

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CAUTION: IMBALANCED TIRE PRESSURE MAY RESULT IN ERACTIC TRAILER OPERATION OR LOSS OF TRAILER CONTROL IF TIRE FAILURE OCCURS WHEN TOWED.

Conversion value: 6.895 kPa = 1 psi

(a) Initial tire rotation should be accomplished by interchanging the

wheel and tire assemblies in a cross; that is, left front to right rear; right front to left rear; right rear to left front, and left rear to right front.

(b) The second tire rotation should be made by interchanging tire and

wheel assemblies.

NOTE: To achieve maximum tire wear, a single pattern of rotation should be used. Inconsistent rotation procedure may contribute to the wear. (c) Inspect all tires and wheels removed for damage. Replace wheels

that are bent or cracked, or that leak air. Check for:

• Excessive tread wear (1/16-inch or less tread remaining).

• Tread or cord or fabric sidewall cracked, cut, split or snagged deep enough to expose the

• A bump, budge, or other indication of ply separation

• An unrepairable puncture

• Bent or dented wheel rims

• Excessive lateral or radial wheel run out

• Wheel porosity

• Elongated or cracked bolt holes in rims

• Mounting surface of rims deformed

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CAUTION: ALWAYS ADHERE TO THE FOLLOWING INSTRUCTIONS:

(1) NEVER ATTEMPT TO STRAIGHTEN BENT RIMS (2) NEVER USE WHEELS WITH ELONGATED OR DAMAGED

SEATS (3) ALWAYS REMOVE CORROSION, DIRT, OR FOREIGN

MATERIAL FROM THE WHEEL MOUNTING SURFACES. (4) DO NOT MIX DIFFERENT TYPES OF TIRES, REPLACE

TIRES THAT ARE NON-UNIFORM IN DESIGN, CAPACITY, SIZE, OR TREADWEAR.

(5) INSTALL NEW TIRES IN AXLE SETS. IF NECESSARY TO

REPLACE ONE TIRE, PAIR IT WITH THE TIRE HAVING THE MOST TREAD.

(6) NEVER ATTEMPT TO REPAIR A WHEEL USING HEAT,

WELDING OR PEENING AND NEVER MUST HEAT TO LOOSEN A TIGHT WHEEL.

(7) TO AVOID BENDING WHEELS, ALWAYS TIGHTEN WHEEL

NUTS IN SEQUENCE.

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COMPONENT INSPECT FOR INTERVAL *1

1. Engine Pre-start checks:

A. Engine crank case oil level When used

B. Engine oil condition When used C. Drive belt condition 250 hours D. Coolant level and condition *2 When used E. Radiator cap condition When used F. Battery and cable condition When used G. Fuel/water separator, drain as required. When used H. Fuel Leaks When used I. Oil Leaks When used J. Cooling system leaks When used

K. Air filter condition When used 2. Engine Start-up Checks:

A. Exhaust color normal When used

B. Oil leaks visible When used C. Fuel leaks visible When used D. Exhaust gas leaks present When used

E. Abnormal engine noise When used 3. Pre-operation Checks:

A. Parking brake operation When used

B. Fuel tank level adequate When used C. Check tire pressure and tread for cuts, bruises,

nails and foreign objects. Inspect rims for damage. *3

When used

D. Access panels in place and secure When used E. Engine cover latches installed and in good

condition. When used

F. Fasteners are not missing When used G. Wheel chocks installed When used H. Check all gauges, switches, and instruments for

proper operation When used

I. Check tow bar, brake assembly, and steering hub for binding or other damage.

When used

J. Inspect body panels for rust, dents, exposed metal areas requiring paint

When used

K. Visually inspect the condenser coil When used L. Check evaporator coil box drain When used

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4. Engine System:

A. Empty air filter dust collection cup 25 hours

B. Check engine air filter restriction gauge. *4 Clean or replace a clogged air filter

Weekly

C. Drain sediment and water from the fuel tank 500 hours D. Check the exterior of the fuel tank for damage and

mount security, fuel hose condition, and security of clamps and fasteners. *5

Monthly

E. Inspect all cooling system hoses for serviceable condition. *5

500 hours

F. Test the engine coolant for depletion of corrosion inhibitors, dilution, and contamination

200 hours

G. Check the alternator drive belt tension. *6 500 hours H. Check exhaust pipes for damage and security of

exhaust system connections and fasteners. Tighten or replace as required

Biannually

I. Empty accumulated carbon from the muffler Biannually J. Inspect the turbocharger for leaks, unusual noise,

or vibration When used

K. Load test the battery Biannually L. Inspect battery for corroded terminals and dirty

case. Clean as required. *7 Monthly

M. Check engine water pump for damage and leaks. Clean the water pump drain hole.

500 hours

N. Check engine oil pressure 500 hours O. Pressure check fuel injection nozzles Annually P. Check valve clearance. *8 1000 hours or

12 months R. Check cylinder compression. *9 Annually S. Check engine mounts for security of attachment,

cracks, or breaks Annually

T. Check the condition of the starter motor brushes and armature. Check for the presence of dirt, or other foreign matter, clean tight connections, excessive circuit resistance, operation of drive and solenoid.

Annually

U. Check alternator output for 13.7 – 14.2 volts Monthly

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5. Generator: A. Check all cables and wiring for broken worn, or damaged insulation Visually inspect insulation for:

.

Biannually

1. Deterioration from thermal aging 2. Abrasion from the physical contact of moving

parts.

3. Cracking from mechanical stress. 4. Erosion by foreign particles drawn into the

generator by the cooling fan.

B. Check all terminal connections for security of attachment

Biannually

WARNING: THESE PROCEDURES SHOULD BE PERFORMED ONLY BY QUALIFIED PERSONNEL. THE FOLLOWING SERVICE AND FAULT FINDING PROCEDURES PRESENT HAZARDS WHICH CAN RESULT IN SEVERE PERSONAL INJURY OR DEATH.

C. Check winding condition Annually D. Check for evidence of overheating, excessive

noise, and vibration Annually

E. Check generator frequency, phase voltage, and current readings

When used

6. Trailer: A. Check the tightness of lug nuts Monthly B. Check for smooth operation of the tow bar and

freedom from damage When used

C. Check for loose, damaged, or corroded hardware Annually 7. Delivered Air System:

A. Check for damaged or dirty inlet filter When used

B. Check blower for excessive noise of vibration When used C. Check fan wheel for cracks and metal fatigue 250 hours

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8. Refrigeration System:

A. Visually inspect the condenser coil for accumulated dirt and oil deposits, obstructed, or damaged fins, corrosion, and leakage. *10

Monthly

CAUTION: DO NOT USE A CLEANER THAT WILL DAMAGER ALUMINUM OR COPPER. DO NOT USE CLEANING SOLVENTS. THESE COMPOUNDS LEAVE AN OILY FILM THAT RETARDS HEAT TREANSFER.

B. Check the condenser fan for smooth, regulated operation and freedom from vibration. Check the vibration level using a meter. *11

Biannually

C. Inspect piping and fittings for visible evidence of refrigerant oil, indicative of leaks. Leak check the refrigeration system.

Inspect when used and leak check biannually or whenever leakage is suspected or indicated.

WARNING: NEVER LEAK TEST USING A PRESSURIZED MIXTURE OF HFC-134A AND AIR.

D. Check the refrigeration system for the presence of noncondensable gases and moisture. *12

Biannually

E. Check the refrigerant charge level. *13 Biannually

F. Check compressor oil level *13 Biannually 9. Electrical Systems:

A. Check all wiring for damaged, chafed, or deteriorated insulation, breaks, security of attachment

Biannually

B. Check for cracked or broken terminal strips, security of attachment, security of attached electrical leads

Biannually

C. Check for proper operation of all switches, security of attachment

Monthly

D. Check relays and sockets for security of attachment

Monthly

E. Check the condition of all circuit breakers and fuses.

Monthly

F. Check all lights for proper operation and defective bulbs, cracked lenses, security of attachment.

Daily

G. Check battery terminals for corrosion Monthly

H. Check for normal system operation Daily Pro

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*1 This operation should be performed at more frequent intervals under dusty or low temperature conditions. The time schedules indicated in Chart 3 are approximate and are based on average conditions. Reduction of the interval shown may be necessary under harsh operating conditions such as low engine temperature, excessively heavy loads, and high oil temperatures, or operation in particularly arid or dusty environments.

*2 Add a mixture of 50% ethylene glycol antifreeze concentrate and 50% soft water until ¾-inch

below the filler neck, maintain level above ‘full cold’ in the overflow tank. *3. Fill the tires to the air pressure indicated on the trailer frame adjacent to each wheel. *4 Maximum allowable restriction is 25 inches of water (6.2 kPa). Filter condition is indicated by

the restriction gauge installed on the air filter housing. *5 All hoses should be replaced during major overhaul or after 5 years maximum service.

Replace the fuel return hose after a maximum of two years service. *6 The engine is equipped with an automatic belt tensioner. Inadequate tension may be due to

excessive belt wear. *7 Coat the terminals with a commercial anti-corrosion spray or petroleum jelly. *8 Adjust initially after 1000 hours or 12 months; then, every 2,000 hours or 2 years. *9 Check as a routine part of maintenance when recomissioning a unit that has been idle for an

extended period. Check in accordance with the manufacturer’s instruction. *10 Clean or repair the coil as required. *11 Repair or replace an imbalanced fan if vibration level exceeds 6 mils. *12 Purge or evacuate the gases and moisture from the system. *13 Refer to the compressor manufacturer’s instructions contained in Chapter 5.

Chart 3- Maintenance Intervals

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I- TOOLS AND FIXTURES

(1) General

The following special tools or fixtures are available from TLD, Windsor, Connecticut or may be purchased directly from the tool manufacturer or authorized distributor. If the tool or fixture may be fabricated by the customer, material specifications and dimensions are provided. This section contains special tools, test equipment, and consumable items needed for the removal, disassembly, inspection, assembly, installation and testing of components. Observe the follow guidelines for safe tool use:

• Use the correct tool for the job.

• Keep tools and equipment properly maintained

• Keep guards in place.

• Keep the work area clean.

• Store tools when not in current use.

• Wear protective clothing, safety glasses, or face guard, dust mask or respirator.

• Secure work to prevent unexpected movement.

• Never force tools. Let the tool work at its own rate. Keep cutting tools sharp.

• Don’t overreach.

• Pull on wrenches. Don’t push.

• Hold sharp or pointed tools away from your body.

• Ground all power tools.

• Ensure that the work area is well lighted and properly ventilated.

• To prevent injury from slipping, use only the correct size socket wrenches.

• Always keep a well-maintained first air kit available for immediate treatment of minor injuries.

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(2) Basic Tools and Equipment

In order to satisfactorily analyze, trouble shoot and maintain the refrigeration system, a minimum amount of service tools is required. The following chart shows the minimum amount of service tools required for servicing a single unit.

TLD PART

NUMBERNAME AND DESCRIPTION REMARKS

40112

1019642

Refrigerant charging kit including” (1) 10034 suction gauge (1) 10042 discharge gauge (1) 38027 gauge manifold (3) 1003916 charging hoses, ¼ in i.d. Electronic leak detector

Refrigerant charging for test purpose To detect refrigerant leaks

Chart 4- Service Tools—Single Units

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The chart below lists additional tools that are available and are desirable for ease of system maintenance. These tools should be obtained when multiple units are to be properly maintained.

TLD PART

NUMBERNAME AND DESCRIPTION REMARKS

84146

1019642

ACE-233

Evacuation Kit (1) 52032A Vacuum gauge, 0-11,000 microns, portable, with gauge tube and connection. (2) 10073A Gauge tube for vacuum gauge 52032 (1) 33008 Vacuum pump, 5.6 cfm, 0.1 micron (1) 59398 Vacuum hose, ¾ i.d., bronze, 10 feet long (1) 84104 Kit-Evacuation Adapter These items are supplied interconnected and mounted on a convenient pushcart. Electronic leak detector Portable pressurized oiler

To Evacuate the refrigeration system To detect refrigerant leaks To add oil in the compressor when the system is pressurized.

Chart 5- Service Tools—Multiple Units

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II- TROUBLESHOOTING

1- GENERAL

The charts included in this section provide troubleshooting guides to assist in the determination and correction of possible unit malfunctions. The charts provide troubleshooting data relative to the unit mounted systems only and do not cover troubles directly related to the basic engine, generator, and other vendor-supplied components. Such information should be acquired from the applicable manufacturer or vendor. Before troubleshooting the unit and its associated components, the technician shall always verify the following: that serviceable fuses and circuit breakers are installed, that continuity exists; that the unit battery is fully charged; that there are no defective lamp bulbs, loose connections, broken wires, frayed insulation, or corrosion in the electrical circuits; and that no leakage occurs in the lines and/or fittings before attempting to diagnose a system problem. A- ENGINE SYSTEM TROUBLESHOOTING

Troubleshooting data for the engine system is provided in Chart 4. Refer to the engine manufacturer’s instruction in Chapter 5 for additional information.

B- GENERATOR TROUBLESHOOTING

Troubleshooting data for the generator is provided in Chart 5. Refer to the generator manufacturer’s instructions in Chapter 5 for additional information.

C- REFRIGERATION SYSTEM TROUBLESHOOTING

Troubleshooting data for the refrigeration system is provided in Chart 6. The flow diagram is contained in Chapter 2, Section 2.

D- ELECTRICAL SYSTEM TROUBLESHOOTING

Troubleshooting data for the electrical system is provided in Chart 7. The electrical system schematics and connection diagram are contained in Chapter 2, Section 2.

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2- TROUBLESHOOTING CHARTS

Trouble Probable Cause Remedy A Genset control switch

not in the “Auto” Position.

A Turn Genset control switch to “Auto”

B Poor battery cable connections.

B Clean the battery cable terminals and tighten all connections.

C Discharged or defective battery

C Recharge or replace the battery.

D Loose or dirty battery connection.

D Clean and tighten connection.

E Defective or open 15 amp control circuit fuse.

E Replace fuse and determine the cause for circuit overload.

F Defective starter solenoid.

F Replace defective starter solenoid.

G Defective start relay G Replace defective start relay

1. Engine fails to crank when the unit control switch is rotated to “I”

H Optional transfer switch not in “genset” position.

H Place transfer switch in “genset” position.

A Empty fuel tank, fuel leak, or obstructed fuel lines.

A Service the fuel tank, repair or replace leaking or obstructed fuel lines and connections

B Clogged fuel filter. B Replace the and fuel filter elements.

C Defective fuel pump. C Refer to the genset manufacturer’s instructions.

D Defective fuel injector (s).

D Refer to the genset manufacturer’s instructions.

E Restricted or pinched fuel line.

E Repair or replace restricted fuel line.

F Low compression due to worn or maladjusted valves, piston rings/liners, leaking head gaskets.

F Determine cause for low compression and repair the engine. Refer to the genset manufacturer’s instruction.

2. Engine cranks, but fails to start when the unit control switch is rotated to “I”

G Air in fuel system G Bleed air from the fuel system. Refer to the genset manufacturer’s instruction. Pro

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A Fuel system air

locked. A Refer to the genset

manufacturer’s instructions for bleeding air from the fuel system.

B Malfunctioning engine shutdown device

B Check generator display panel for shutdown faults. Correct as needed. Refer to genset manufacturer’s instructions.

3. Engine starts, but will not continue running.

C Fuel contaminated. C Drain contaminated fuel and fill tank with fresh, clean fuel of the recommended grade. Refer to the genset manufacturer’s instructions.

A Battery discharged, or loose connections.

A Check battery charge. Recharge or Replace battery. Check all battery and cable connections.

B Defective starter motor solenoid.

B Repair or replace the starter motor solenoid. Refer to the engine manufacturer’s instructions.

C Defective starter motor.

C Repair or replace the starter motor. Refer to the engine manufacturer’s instructions.

4. Engine cranks slowly.

D Improper viscosity lubricating oil.

D Refer to the engine manufacturer’s recommendations.

A Airflow restricted. A Inspect the engine air filter and clean or replace as required.

B Maladjusted or defective engine

B Refer to the engine manufacturer’s instructions.

C Exhaust system restrictions.

C Determine and correct exhaust system restriction.

D Excessive fuel or irregular fuel distribution.

D Refer to the engine manufacturer’s instruction

E Improper engine adjustments.

E Refer to the engine manufacturer’s instructions.

5. Engine will not reach rated speed under load.

F Engine Overloaded F Verify unit control system is operating unit in desired mode only.

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A Defective engine

thermostat. A Test thermostat and replace

as necessary. B Coolant level low. B Add coolant to the

recommended level. C Radiator fins damaged or

obstructed. C Clean or repair the radiator.

D Radiator hose collapsed. D Replace a defective hose. E Engine oil level incorrect. E Add or drain oil as required. F Slipping or broken fan

belt. F Replace a broken or

damaged drive belt.

6. Engine overheats

G Radiator cap defective G Replace defective cap. A Incorrect or defective

thermostat. A Refer to the engine

manufacturer’s instructions. Test and replace a defective or incorrect heat range thermostat.

7. Engine temperature too low

B Incorrect or defective heating mode thermostat (symptom only when operating in heating mode)

B Replace thermostat and verify engine operates at 170°F (77°C) or higher in heating mode.

A Low coolant level. A Check coolant level and replenish if low. Inspect cooling system for leaks and repair if necessary.

B Poor radiator airflow B Check for obstructed cooling airflow and correct as necessary.

8. Engine shuts down due to high engine temperature.

C Defective or slipping engine serpentine belt.

C

Check for defective engine serpentine belt and/or tensioner. Replace as necessary.

A Low engine oil level. A Check oil level, lines and filters. If the lubrication system is leak-free, replenish oil level.

9. Engine shuts down due to low oil pressure.

B Low engine oil pressure. B Verify engine oil pressure with a mechanical gage. Repair engine as necessary.

A External leakage from hoses, fittings, or gaskets.

A Inspect all hoses, fittings, and gaskets and tighten or replace them as necessary.

B Excessive crankcase pressure.

B Verify engine breather hose is not clogged or collapsed.

C Internal oil leaks from oil cooler, or worn exhaust guides.

C Refer to the engine manufacturer’s instructions.

10. Engine losing oil.

D Excessive oil in the crankcase.

D Refer to the engine manufacturer’s instructions.

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A Insufficient fuel. A Verify engine fuel filters are

not clogged. Replace as necessary.

B Faulty injectors. B Refer to the engine manufacturer’s instructions.

C Low compression pressures.

C Refer to the engine manufacturer’s instructions.

11. Engine operation uneven or frequent stalling.

D Engine Control Module problem

D Refer to the engine manufacturer’s instructions.

A Serpentine drive belt loose or damaged.

A Replace a damaged drive belt, verify tensioner operation.

B Defective alternator B Repair or replace the alternator.

C Exhaust gas leak. C Repair the exhaust system. D Air intake system leaking

or damaged. D Repair air intake system.

E Loose, rubbing, or vibrating components.

E Locate vibrating components and correct the cause of vibration.

12. Unusual engine noises.

F Internal engine damage or excessively worn components.

F Refer to the engine manufacturer’s instructions.

Chart 6- Engine Troubleshooting

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WARNING: HIGH VOLTAGES ARE PRESENT AT THE GENERATOR TERMINALS. SERIOUS PERSONAL INJURY OR DEATH CAN RESULT FROM CONTACT WITH ROTATING PARTS OR LIVE ELECTRICAL CONNECTIONS DURING OPERATION. TESTING SHALL BE PERFORMED ONLY BY QUALIFIED MAINTENANCE PERSONNEL.

Trouble Probable Cause Remedy A Defective Generator

Controller A Refer to the genset

manufacturer’s instructions. 1. No voltage.

B Defective Genset Alternator

B Refer to the genset manufacturer’s instructions.

A Engine not running at correct speed

A Check engine speed and restore to correct rpm.

B Low voltage setpoint in generator controller

B Refer to the generator manufacturer’s instructions.

C High resistance connection

C Clean and tighten connections

2. Low voltage.

D Weak field due to high ambient temperature operation.

D Open engine doors to improve ventilation.

A Engine not running at correct speed.

A Check engine speed and restore to correct rpm.

3. High Voltage.

B High voltage setpoint in generator controller

B Refer to the manufacturer’s instructions.

A Clogged ventilating screens and air passages.

A Clean all screens and air passages.

B Dry or defective bearings B Replace defective bearings.

4. Overheating.

C Generator filed coils shorted or grounded.

C Test field coils for shorts. Replace shorted rotor.

A Generator mounts loose or defective.

A Tighten mounting fasteners securely. Replace a defective vibration isolator.

B Engine mounts loose or defective.

B Tighten mounting fasteners securely. Replace defective vibration isolators.

5. Vibration.

C Defective or dry bearing. C Replace defective bearing. A Check for drop in engine

speed on load. A Refer to the engine

manufacturer’s instructions. 6. Excessive voltage drop on load.

B Defective Generator Controller

Refer to the generator manufacturer’s instructions.

Chart 7- Generator Troubleshooting

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Trouble Probable Cause Remedy

A Main circuit breaker open A Reset main circuit breaker. B No control system input

voltage B Check the trip indicator and

reset the control system circuit breaker (Q5) if open.

C Defective 24VDC Control system power supply (U1)

C Check input voltage at L1 and L2 terminals. Check output voltage is 23-25V. Replace as necessary.

1. Refrigeration unit inoperative

D Power quality monitor (U2) tripped.

D Check line voltage adjustment. Check for voltage imbalance, phase loss, or incorrect phase sequence and correct the sensed fault condition.

A Low pressure control has tripped.

A Leak check, repair, evacuate, and recharge as necessary. Check low pressure control operation.

B High pressure control has tripped.

B Check for non condensable gases in system. Evacuate as needed. Check high pressure control operation. Verify unit is not overcharged.

C Compressor circuit breaker open or defective.

C Reset circuit breaker. Check for cause of overload and correct.

D Evaporator coil freezing up during low ambient. Refrigeration charge low.

D Clean or replace air inlet filter. Leak check, repair, evacuate, and recharge the system as necessary.

E Filter/drier supersaturated. Ice formation blocking expansion valve.

E Replace the filter/drier. Leak check, repair, evacuate, and recharge the system as necessary.

2. Unit will not cool, blower fan motor operative.

F Compressor overload or failure.

F Test compressor. Replace if defective. Leak check, repair, evacuate, and recharge the system as necessary.

3. Blower fan motor inoperative.

A Blower contactor open or defective.

A Repair or replace the contactor. Check the cause of thermal overload and correct. Pro

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A Air or noncondensable

gas in the condenser A Leak check, repair, evacuate,

and recharge the system. B Dirty condenser coil,

restricting air flow. B Clean the condenser coil.

4. High compressor discharge pressure.

C Overcharged system. C Check subcooling. Recover excess charge as required.

A High compressor discharge pressure.

A Refer to Paragraph 4.

B Low compressor suction pressure.

B Refer to Paragraph 6.

C Defective high/low pressure control.

C Replace defective pressure control.

D Obstruction in front of condenser coil.

D Remove the obstruction.

5. Compressor fails to stay engaged.

E Compressor winding overheated / Compressor protection module defective.

E Verify compressor has not been started more than once every 3 minutes. Verify lamp on compressor protection module is green.

A Restricted filter/drier. A Replace the filter/drier. Leak check, repair, evacuate, and recharge the system.

B Shut off valve (V4) not fully open

B Open valve (V4)

C Thermal expansion valve (V1) blocked, damaged, or maladjusted.

C Repair or replace a blocked or damaged valve (V1). Refer to Chapter 3, Section 3 for adjustment.

6. Low compressor suction pressure.

D Condenser tubing restricted due to physical damage.

D Repair or replace the condenser coil.

7. High suction pressure.

A

Defective or maladjusted thermal expansion valve (V1).

A Repair or replace a defective thermal expansion valve (V1). Refer to Chapter 3, Section 3 for valve (V1) adjustment.

8. Low discharge pressure.

A Inadequate refrigerant charge

A Leak check, repair, evacuate, and recharge the system.

Chart 8- Refrigeration Troubleshooting

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Trouble Probable Cause Remedy

A High circuit resistance. A Clean and tighten battery connections.

B Low battery charge. B Charge battery.

1. Low battery output.

C Damaged battery. C Replace damaged battery. A Lights or accessories

left on. A Make certain that switches are

off before leaving the unit. 2. Low battery charge

B Defective alternator B Repair or replace the alternator. A High resistance in the

charging circuit connections.

A Inspect circuit for loose or corroded connections. Clean and tighten as required.

B Defective wiring. B Locate broken or undersize wire.

C Poor alternator ground. C Clean ground connection.

3. Low charging circuit voltage.

D Defective alternator. D Repair or replace the alternator. A Slipping drive belt. A Refer to the engine

manufacturer’s instructions. 4. Low charging circuit output

B Defective alternator. B Repair or replace the alternator. A High resistance in

battery connections A Clean and tighten connections. 5. High charging circuit

voltage. B Defective alternator

regulator. B Replace defective regulator

A Defective or worn drive belt.

A Replace drive belt.

B Worn or defective bearings.

B Replace bearings.

6. Noisy engine alternator

C Loose mount or drive pulley.

C Tighten mount and pulley

A Low battery charge. A Charge battery. B High circuit resistance. B Clean and tighten all

connections. Repair or replace faulty wiring

7. Sluggish starting motor operation

C Defective starting motor.

C Repair or replace the starting motor as required.

A Defective ignition switch.

A Replace defective switch.

B High resistance in starting circuit or defective wiring.

B Clean and tighten all connections and replace faulty wiring.

C Defective solenoid switch.

C Replace defective switch.

8. Starting motor inoperative.

D Defective starting motor.

D Repair or replace the starting motor.

9. Starting motor solenoid switch stutters

A Low battery charge. A Charge battery.

Chart 9- Electrical Troubleshooting

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3- USING THE SCHEMATIC AND CONNECTION DIAGRAMS

A- COMPONENT CODE

All components on the schematic and connection diagrams carry a designation number (e.g., D1, M1), which aids in identifying and discussing specific items. The codes are as follows: BT……………………………………………. Battery C……………………………………………… Major component or capacitor D……………………………………………… Diode F……………………………………………… Filter, fuse, or cooling fan G……………………………………………... Gauge H……………………………………………. Light HR……………………………………………. Heater KA…………………………………………… Relay KM…………………………………………… Contactor L……………………………………………… Solenoid or governor relay M……………………………………………… Motor or meter P……………………………………………… Access port, plug Q……………………………………………. Circuit Breaker R……………………………………………… Resistor, rheostat, or sender S……………………………………………… Switch TB……………………………………………. Terminal block V……………………………………………… Valve X……………………………………………… Receptacle

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III- REMOVAL/INSTALLATION

1- GENERAL

Removal of components from the unit should only be done in order to accomplish required repairs or for the purpose of component replacement. If extensive removal of components is required, photographs should be taken and/or sketches made prior to removal. Photographs and/or sketches of the particular installation involved will aid orientation of components at reinstallation Electrical conductors and hydraulic hose assemblies should always be tagged or labeled to facilitate marking the correct connections during reinstallation The procedures and instructions provided in this section should be followed only as far as the particular replacement or repair dictates and are intended primarily as a guide in assisting the mechanic in the performance of an unfamiliar task. It is important to note that this manual contains various “CAUTIONS” and “WARNINGS” that must be carefully observed in order to reduce the risk of personal injury service or repair procedures, or the possibility that improper procedures may render the unit unsafe. It is also important to understand that these “CAUTIONS” and “WARNINGS’ are not exhaustive, since it is impossible to warn of all the possible hazardous consequences that might result from failure to follow these instructions. The following warnings and cautions should be observed during removal and installation procedures.

WARNING: DISCONNECT THE UNIT BATTERY POSITIVE (+) AND NEGATIVE (-) CABLES PRIOR TO MAKING ANY ELECTRICAL SYSTEM REPAIRS. DISCONNECT THE NEGATIVE CABLE FIRST; THEN DISCONNECT THE POSITIVE CABLE. RECONNECT THE NEGATIVE CABLE LAST. FOR ADDITIONAL SAFETY DURING OPERATIONAL CHECKS OF THE UNIT, DEPLOY AN ASSISTANT AT THE INSTRUMENT PANEL READY TO SHUT DOWN THE ENGINE SHOULD AN EMERGENCY CONDITION ARISE. KEEP CLOTHING AND BODY CLEAR OF ALL ROTATING AND HOT EQUIPMENT TO AVOID POSSIBLE PERSONAL INJURY. ALWAYS WEAR PROTECTIVE FACE SHIELD OR SAFETY GLASSES DURING REPAIR OF SPRING-LOADED COMPONENTS. TO AVOID SEVERE FROSTBITE OR EYE DAMAGE, ALWAYS WEAR A FULL-FACE GUARD, CHEMICAL SPLASH GOGGLES, LINED BUTYL GLOVES, AND PROTECTIVE CLOTHING TO PREVENT EXPOSURE TO LIQUID REFRIGERANT.

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USE WHEEL CHOCKS TO AVOID POSSIBLE PERSONAL INJURY OR DAMAGE TO EQUIPMENT. ALWAYS ENGAGE THE PARKING BRAKE TO AVOID POSSIBLE INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT. ALWAYS RELIEVE PRESSURE FROM THE SYSTEM OR ISOLATED SECTION BEING REPAIRED BEFORE ATTEMPTING DISASSEMBLY. DO NOT DISASSEMBLE PRESSURIZED COMPONENTS. USE CORRECT LIFTING EQUIPMENT AND TECHNIQUES. STAY OUT FROM UNDER SUSPENDED LOADS TO ABOVE POSSIBLE PERSONAL INJURY. NEVER RELY SOLELY ON A HYDRAULIC JACK FOR SUPPORT. ALWAYS INSTALL JACK STANDS TO AVOID POSSIBLE PERSONAL INJURY FROM HYDRAULIC JACK SLIPPAGE. NEVER ATTEMPT TO LIFT HEAVY PARTS OR COMPONENTS WITHOUT ASSISTANCE. LIFT ONLY USING PROPER EQUIPMENT AND TECHNIQUES. TO AVOID THE RISK OF POSSIBLE PERSONAL INJURY, USE A POWER HOIST WHENEVER POSSIBLE FOR LIFTING. STAY OUT FROM UNDER SUSPENDED LOADS. TO PREVENT POSSIBLE INJURY, MAKE CERTAIN OIL FILM AND GREASE DEPOSITS ARE CLEANED FROM HEAVY COMPONENTS BEFORE ATTEMPTING REMOVAL.

CAUTION: PURGING OF REFRIGERANT TO ATMOSPHERE IS ILLEGAL AND VIOLATES FEDERAL EPA (ENVIRONMENTAL PROTECTION AGENCY) LAWS AND REGULATIONS. ALWAYS RECOVER AND RECYCLE REFRIGERANTS. ALWAYS OBSERVE THE DIRECTION OF CONTROLLED FLOW ARROWS WHEN REINSTALLING CHECK VALVES AND FLOW CONTROL VALVES IN ANY CIRCUIT. ALWAYS TIGHTEN FASTENERS TO THE RECOMMENDED TORQUE VALUE WHEN REINSTALLING COMPONENTS. PULL BACK ALL HOSES, LINES, AND ELECTRICAL WIRING AND TIE THEM OFF TO PREVENT DAMAGE DURING ENGINE REMOVAL.

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NOTE: Cleanliness is of extreme importance when disconnecting or removing fuel and air intake lines. Cap, plug or cover all lines and fittings after they are disconnected to prevent the entry of contaminants. A- REMOVAL INSTRUCTIONS

(1) Before removing any component, refer to Chapter 2, Section 2, and

“Troubleshooting.” first to isolate the problem. (2) Before removing any component, make certain that the system in which it

is located is not energized or pressurized. Disconnect the battery ground cable and ensure that all controls are in the “OFF” position before starting the removal procedure.

(3) Before removal of any component in the plumbing system, first refer to the

Flow Diagram and Schematics contained in Chapter 2, Section2. (4) Ensure that adequate clearance exists for removal of the component.

Disassemble adjacent components and structure as required to provide the necessary working clearance.

(5) Use a chain hoist, fork lift, or other aid when lifting heavier components.

The lifting devise shall be positioned and attached to relieve all strain from the mounting fasteners before they are removed.

(6) To aid installation, affix identification labels to the ends of plumbing

connection, electrical conductors, and engine and supply coolant lines as they are removed or disconnected. Mark parts of similar configuration to ensure correct reassembly and installation.

NOTE: When a refrigeration system component is disassembled or removed, precautions must be taken to prevent the entrance of moisture and air into the system. Air or moisture that enters the system must be removed by evacuation to assure proper system performance.

(7) Prior to removal, note the original position of components. Photograph or

sketch the original installation to aid restoring components to their original positions during reinstallation.

(8) Components, even though defective, should be treated as valuable for their

reclamation or salvage value. (9) Ensure that recovered or reclaimed fluids are not contaminated prior to

reinstallation into the plumbing system.

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B- INSTALLATION INSTRUCTIONS

(1) Make sure that component orientation is the same as when removed. (2) Check all identification tags for correct connection of all lines, electrical

conductors, and hoses. (3) Use only calibrated gauges when verifying component alignment and

adjustment. (4) Operate the unit and inspect components for proper adjustment, leaks,

vibration, noise, or misalignment. Correct any problems. (5) Purge fuel lines as required.

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IV- REPAIR

1- GENERAL

Repair of unit components is normally accomplished by replacement of unserviceable assemblies or components with serviceable units of like manufacturer and design. Repairs accomplished on unit components while covered by the manufacturer’s warranty period shall be at the operator’s discretion. Careless disassembly and attempted overhaul of a component assembly may void the warranty on that particular component. Observe the following general cautions and warnings:

WARNING: ADEQUATE VENTILATION MUST BE PROVIDED TO PREVENT ACCUMULATION OF HAZARDOUS GASES AND VAPORS. VENT ENGINE EXHAUST DIRECTLY OUTSIDE THROUGH FLEXIBLE TUBING TO AVOID ACCUMULATION OF CARBON MONOXIDE GAS. USE ONLY EXPLOSION-PROOF ELECTRICAL EQUIPMENT. ENSURE THAT ALL ELECTRICAL POWER EQUIPMENT IS PROPERLY GROUNDED. ENSURE THAT ADEQUATE PRECAUTIONS ARE TAKEN TO PREVENT THE BUILD UP OF STATIC ELECTRICITY. NEVER PLACE TOOLS WHERE THEY MAY FALL AND CAUSE AN ELECTRICAL SHORT OR BE THROWN OR PULLED INTO MOVING BELTS OR DRIVES. ALWAYS USE A LIFTING AID SUCH AS AN ELECTRIC HOIST, FORK LIFT TRUCK, HYDRAULIC JACK, OR ADDITIONAL PERSONNEL TO RAISE OR POSITION HEAVY COMPONENTS. USE A PORTABLE DOLLY TO TRANSPORT HEAVY OR BULKY COMPONENTS WHEN HANDLING COMPONENTS AND MATERIALS. OBSERVE THE FOLLOWING PRECAUTIONS: • INSPECT MATERIALS FOR SLIVERS, JAGGED OR SHARP EDGES,

BURNS, ROUGH, OR SLIPPERY SURFACES. • ALWAYS GRIP OBJECTS FIRMLY. • KEEP FINGERS AWAY FROM PINCH AND SHEAR POINTS. • CLEAN GREASE, OIL, WATER, AND DIRT FROM COMPONENTS

BEFORE ATTEMPTING RO REMOVE OR INSTALL THEM. • KEEP HANDS FREE OF OIL AND GREASE.

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• ALWAYS USE APPROVED SCAFFOLDING FOR SAFE ACCESS TO ELEVATED WORK AREAS.

• IMPERVIOUS PROTECTIVE CLOTHING SHOULD BE WORN WHEN HANDLING HAZARDOUS MATERIALS.

• NEVER WEAR GLOVES OR LOOSE CLOTHING WHEN WORKING WITH ROTATING OR MOVING MACHINERY.

CAUTION: ONLY PROPERLY TRAINED AND QUALIFIED PERSONNEL SHOULD OPERATE ANY MATERIAL HANDLING EQUIPMENT. BEFORE OPERATION ANY MATERIAL HANDLING EQUIPMENT, ENSURE THAT IT HAS BEEN PROPERLY MAINTAINED AND SERVICED. INSPECT ALL CRANES AND HOISTS FOR PROPER INSTALLATION, MAINTENANCE, AND SUITABLE CAPACITY. (1) Remove nicks, burrs, or scratches from surfaces in contact with gaskets,

packings or seals using a fine file or medium grit emery cloth. (2) Replace hoses with broken or frayed fabric cover, damaged fitting threads,

breaks, or leaks. (3) Replace all cracked or burned electrical components and all wires on which

several strands are broken. (4) Replace all damaged screws, nuts and fittings. Do not change size or thread

type. All self-locking fasteners and split lock washers should be replaced after one use.

(5) Cracked, chipped, or peeling paint can be restored using standard shop

procedures.

CAUTION: Protect adjacent surfaces from abrasive dust and paint overspray by masking or covering with paper.

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2- GENERAL BRAZING AND SOLDERING INSTRUCTIONS

A- GENERAL

Soldering and brazing share similar techniques and processes in joining copper tube and fittings. The components to be joined are assembled and preheated to a temperature higher than the melting point of the filler metal. The filler metal is then applied to the pre-heated parts where it melts at the tinning temperature and flows into the joint through capillary action. The primary difference between the two methods is that brazing requires a higher preheating temperature. Soldering joins materials using a non-ferrous filler metal having a melting point under 840°F (450°C). Brazing joins materials using a non-ferrous filler metal having a melting point above 840°F (450°C). In both procedures, the filler metal is distributed between closely fitting joints by capillary action. The base metal is not melted in either process. The brazing process produces a stronger joint of greater tensile strength then a soldered joint due to the type of filler metal used and the higher temperatures employed. In both processes, the integrity of the base metal is retained since the lower bonding temperatures required does not destroy the mechanical properties of the base metal. Although soldering and brazing share the same process and similar techniques, they differ in the type of filler metal used, the amount of heat, and the time required in the joining process. Although soldering and brazing share the same process and similar techniques, they differ in the type of filler metal used, the amount of heat, and the time required in the joining process. Soldered joints are acceptable when system temperatures do not exceed 250°F/ Brazed joints can be used when system temperatures reach 350°F. In actual practice, most soldering is done at temperatures ranging from 350°F to 550°F. Brazing is done at temperatures ranging from 1,100°F to 1,550°F.

B- SAFETY PROCEDURES

Observe the following precautions and warnings when performing any joining procedure:

WARNING: ENSURE THE WORKING AREAS, ESPECIALLY CONFINED AREAS, ARE ADEQUATELY VENTILATED. NEVER BRAZE OR SOLDER IN THE PRESENCE OF EXPLOSIVE ATMOSPHERES.

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NEVER BRAZE OR SOLDER IN THE PRESENCE OF COMBUSTIBLE MATERIALS. AVOID BREATHING FUMES PRODUCED DURING BRAZING OR SOLDERING PROCESSES. WEAR A RESPIRATOR WHEN TOXIC FUMES ARE PRESENT IN HARMFUL CONCENTRATIONS. DO NOT BRING PRESSURIZED GAS CYLINDERS INTO CONFINED SPACES. SHADED EYE PROTECTION SHALL BE WORN DURING TORCH BRAZING PROCEDURES. OPEN ALL CYLINDER VALVES SLOWLY. PROTECTIVE CLOTHING SHALL BE WORN DURING TORCH BRAZING PROCEDURES. FLUX, WHEN HEATED, MAY PRODUCE NOXIOUS OR TOXIC FUMES THAT CAN IRRITATE THE EYES, NOSE AND THROAT. AVOID CONTACT OF FLUX WITH SKIN OR EYES. USE HEAT SHIELDS OR FLAME RESISTANT INSULATION TO PROTECT COMPONENTS, TANKS, LINES, AND ELECTRICAL WIRING IN THE WORK AREA FROM POSSIBLE CONTACT WITH OPEN FLAME. PROTECT ADJACENT PARTS FROM HEAT BY WRAPPING WET RAGS AROUND THE COMPONENTS.

CAUTION: RECOVER THE REFRIGERANT BEFORE ATTEMPTING ANY REPAIR PROCEDURE. ALWAYS RECLAIM REFRIGERANT PRESSURE FROM THE REPAIR AREA. ALWAYS USE APPROVED RECLAMATION METHODS WHEN RECLAIMING REFRIGERANT PRESSURE. EVACUATE OR RECLAIM AND RECHARGE THE ISOLATED SECTION OR SYSTEM PRIOR TO RECHARGING WITH REFRIGERANT.

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NOTE: Prepare the metal by first removing paint, dirt, or foreign matter with a wire brush, emery cloth, or steel wool. Wipe the surface of the metal with a clean dry cotton rag. Ensure that soldering or brazing equipment is clean and in serviceable condition before use. Verify the correct operation of the shut-off valves. Ensure that the orifice is clean and functions properly. Install the correct orifice and tip for the intended work. Do not repair joints with discontinuities by remelting and adding additional brazing material. Always braze the joint, clean thoroughly, and then debraze the joint.

C- BASIC JOINING PROCEDURE

(1) Tube runs must be measured accurately to ensure that the tube will bottom in the fitting socket. If the tube will not extend fully into the socket, a proper joint cannot be made.

(2) Tubing must be cut squarely in order to seat properly in the fitting socket.

Tubing may be cut using a disc type tubing cutter, a hacksaw, abrasive wheel, or band saw.

(3) Use a deburring tool to ream the end of the cut tube. Unless the rough

edges are removed, irregular flow due to local turbulence and increased velocity may result. A properly reamed tube will provide smooth, unrestricted flow through the joint.

(4) The parts to be joined must be clean in order to assure a strong joint free

from discontinuities. The removal of oxides and surface soil is crucial if filler metal is to flow properly. Oxides, surface soil, and oil film can interfere with the strength of the joint and result in failure. The parts can be cleaned mechanically using sanding cloth or nylon abrasive pads.

CAUTION: EXCESSIVE REMOVAL OF MATERIAL WILL RESULT IN A LOOSE FIT (OVER .005 IN.) AND INTERFERE WITH SATISFACTORY CAPILLARY ACTION, PRODUCING A WEAK JOINT.

NOTE: Parts may be chemically cleaned to neutralize acids and remove oxidation. Parts should not be handled once they are cleaned. Oils on the hands and in the skin may impair solder flow and flux wetting action.

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3- ELECTRICAL SYSTEM REPAIRS

A- ELECTRICAL SAFETY

(1) Observe the following practices and work habits when repairing or servicing electrical systems and their components:

• Lock out or disconnect the electrical power source from the system

before beginning service procedures.

• Wear protective clothing and eyewear when working with storage batteries.

• Always read, understand, and follow the unit operating and

maintenance manual.

• Read and understand labeling and safety symbols on the equipment.

• Make sure that wires are properly insulated, clean, and free from accumulated debris.

• Become skilled in the basic rules of first aid and keep first aid supplies

on hand for emergencies.

• Work only in well-ventilated and lighted areas.

• Never work alone.

• Never wear jewelry or other metallic objects when working on equipment.

• Use insulated tools.

WARNING: TO AVOID BECOMING PART OF THE CURRENT PATH WHEN WORKING ON A CIRCUIT, ALWAYS KEEP ONE HAND AWAY FROM THE VOLTAGE SOURCE. NEVER OPERATE AN ENGINE WHEN THE ALTERNATOR WIRE IS DISCONNECTED. INSULATE YOURSELF FROM SHOCK IF ATTEMPTING TO MOVE A SHOCK VICTIM AWAY FROM THE VOLTAGE SOURCE. START CPR (CARDIOPULMONARY RESUSCITATION) IF THE VICTIM IS NOT BREATHING.

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(2) The most frequent hazards encountered when servicing automotive type electrical circuits are fires, short-circuit conditions, battery explosions, acid burns, and electric shock. Make sure that all wiring is properly insulated and clean. Observe the following precautions:

• Keep an ABC all-purpose dry chemical fire extinguisher on hand to

dampen flames should a fire develop.

• Wiring with cracked, worn, or damaged insulation should be replaced immediately to eliminate the opportunity for occurrence of short circuits. Terminal posts and wiring connections should be insulated or covered with high dielectric strength guards.

(3) Batteries contain sulfuric acid with explosive mixtures of hydrogen and

oxygen gases. Even maintenance-free, sealed batteries are vented to prevent the build-up of these gases. Observe the following precautions and warnings when working with storage batteries.

WARNING: NEVER CHECK BATTERY CONDITION BY SHORTING ACROSS THE BATTERY TERMINALS WITH A WIRE OR METAL OBJECT. ALWAYS WEAR SAFETY SPLASH GOGGLES AND PROTECTIVE CLOTHING WHEN WORKING AROUND BATTERIES. PROTECT BATTERIES FROM EXPOSURE TO SPARKS AND FLAME. ALWAYS SERVICE BATTERIES IN WELL-VENTILATED AREAS. ALWAYS REMOVE AND REPLACE BATTERY CLAMPS BY REMOVING THE GROUND TERMINAL CLAMP FIRST AND REPLACING IT LAST. TO PREVENT SPARKS FROM BATTERY CLAMPS BY REMOVING THE GROUND TERMINAL CLAMP FIRST AND REPLACING IT LAST. TO PREVENT SPARKS FROM BATTERY CHARGER LEADS, TURN THE CHARGER OFF AND PULL THE POWER CORD BEFORE CONNECTING OR DISCONNECTING CHARGER LEADS TO BATTERY POSTS.

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IF BATTERY ACID CONTACTS THE SKIN, REMOVE THE AFFECTED CLOTHING AND FLUSH THE AREA IMMEDIATELY WITH WATER FOR 5 TO 10 MINUTES. APPLY BAKING SODA TO NEUTRALIZE THE ACID. IF ACID ENTERS THE EYES, FLUSH WITH WATER FOR 15 TO 30 MINUTES, SUMMON MEDICAL AID IMMEDIATELY. IF ACID IS INGESTED, DRINK LARGE AMOUNTS OF MILK OR WATER. DO NOT EXCEED TWO QUARTS (1.89 LITER). SUMMON MEDICAL AID IMMEDIATELY.

B- CIRCUIT WIRING

(1) Connectors

Connectors function in a circuit to transfer current from one set of wires to another. Connectors comprise mating halves that are equipped with male and female contacts or terminals. When the connectors are coupled, the contacts are fully engaged, enabling current flow. The connectors transmit current flow effectively only when the resistance to flow across the terminals is minimized. Resistance to flow through connectors is affected by surface interference, the type of contact material, and contaminants. All electrical connections may cause a discharged battery, difficult starting, dim lighting, and possible damage to the alternator and regulator.

(2) Wire

Wire size in a circuit is determined by the amount of current the length of the circuit and the voltage drop permitted. Wire size is specified using the metric gauge. The metric gauge describes the wire size directly in a cross-section area measured in square millimeters. When replacing wire, it is important that the replacement wire conform to the size indicated on the unit wiring diagram. Each wire or harness must be secured to prevent chafing or damage to the insulation due to vibration.

CAUTION: NEVER REPLACE A WIRE WITH ONE OF A SMALLER SIZE OR REPLACE A FUSIBLE LINK WITH A WIRE OF A LARGER SIZE. REPLACEMENT WITH THE INCORRECT SIZE MAY CAUSE REPEATED FAILURE AND DAMAGE TO THE ELECTRICAL SYSTEM.

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C- SWITCH CONTACTS Pressure switches are sometimes subjected to the harsh conditions of jet blast, exposure to sand, carbon, or oil. A buildup of contaminants on the switch contacts can decrease the reliability of the unit. To assure proper performance, the contacts should be cleaned every 6 months or more often as conditions dictate. Do not use sandpaper or a file to clean the contacts. The contacts are best cleaned with a commercial contact cleaner and a soft cloth.

4- MECHANICAL REPAIRS

A- FASTENERS (1) General

Fasteners are used to join two or more materials. When a bolt is tightened, two forces are applied to the fastener, torsion and tension. Torsion is the force applied as the fastener is rotated against frictional resistance. Tension is the clamping force applied to the material. Torque values are based primarily on the grade or strength classification of a fastener and not solely on size.

CAUTION: DO NOT USE THESE VALUES IF A DIFFERENT TORQUE VALUE OR TIGHTENING PROCEDURE IS LISTED FOR A SPECIFIC APPLICATION. THE TORQUE VALUES LISTED ARE FOR GENERAL USE ONLY. FASTENERS SHOULD BE REPLACED WITH THE SAME OR HIGHER GRADE AND TIGHTENED TO THE STRENGTH OF THE ORIGINAL. MAKE CERTAIN THAT THE FASTENER THREADS ARE CLEAN AND PROPERLY ENGAGED TO AVOID POSSIBLE FAILURE WHEN TIGHTENED. Prope

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(2) Fastener Grades

Fasteners are graded by the clamping force that they can safely apply to a load. Fasteners are classified by their tensile strength in numerical grades. Corresponding specifications have been established for these grades by SAE, ASTM, industrial/commercial, military and Federal organizations. The grades are arranged according to degree of tensile strength and hardness from SAE Grade 1 through Grade 8 for fractional fasteners and Property Class 5.8 through 12.9 for metric fasteners. The service life span and performance of a fastener is determined by the grade of steel used, the manufacturing process employed the use of the correct size and grade for the application, and correct installation.

(3) Lubrication

Fasteners should be lubricated and tightened using a torque wrench. Lubrication reduces the energy lost in torsional friction. The variables associated with torsional resistance due to damaged threads, excessive plating, corrosion, or dirt can be reduced or eliminated by using a lubricant. Lubricated fasteners at lower torque values can produce greater preloads than non-lubricated fasteners at higher torques.

NOTE: “Lubricated” means coated with engine oil or other lubricant. “Dry” means plain or zinc plated without any lubrication. (4) Tightening Fasteners

Torque is a turning or twisting effort expressed in pound-feet. A pound-foot is the moment created by a force of one pound applied to the end of a lever arm one foot long. Conversely, foot-pound expresses energy expended. A foot-pound is the amount of energy expended in lifting a one-pound weight a distance of one foot against the pull of gravity. Fasteners may be torqued by the lever method or by nut rotation. Whichever method is used, first install fasteners by hand until finger tight; then tighten alternately and evenly to the required torque valve. Pro

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In order to maintain preload in installations requiring gaskets, compression must be removed from the clamped parts to prevent the loss of preload. A minimum of five complete torque applications will be required to achieve adequate preload. Whenever fasteners are lubricated reduce the dry torque value specified for the fastener by 40 percent. Properly tensioned fasteners eliminate shear forces and failure due to fatigue. The critical factor in achieving proper tension is tightening the fasteners enough. Tabulated torque values are based on factory conditions. These conditions cannot be easily duplicated in the field. Therefore, higher grade fasteners should always be substituted for OEM fasteners when replaced in the field. Charts 10 and 11 contain the torque values for the various screws that are used in the unit. All screws should be tightened in accordance with the values given when assembled. Screws at the gasket joints, set screws, and coupling screws should be re-torqued to the given values after approximately 10 hours of operation. If extensions are used, in conjunction with the torque wrench, the proper correction factors must be applied to the given values. Tighten the screws on the tapered bushing to the torque values provided by the bushing manufacturer. Over tightening these screws may result in breakage of the bushing.

SIZE/ TYPE

SAE GRADE 2

SAE GRADE 3

SAE GRADE 5

SAE GRADE 6

SAE GRADE 7

SAE GRADE 8

SOCKET HEAD

SET SCREW

S.S. CAP & MACH.

No. 6 -- -- -- -- -- -- -- 9 lb/in 9.6 lb/in

No. 8 -- -- -- -- -- -- -- 16 lb/in 20 lb/in

No. 10 -- -- -- -- -- -- -- 30 lb/in 23 lb/in

¼ 6 9 9 12.5 12.5 13 14 70 lb/in 75 lb/in

5/16 11 17 18 24 24 28 30 12 11

3/8 19 30 31 43 43 46 50 18 20

5/16 11 17 18 24 24 28 30 12 11

3/8 19 30 31 43 43 46 50 18 20

7/16 30 47 50 69 69 75 81 29 31

½ 45 69 75 106 106 115 121 43 43

9/16 66 103 110 150 150 165 176 63 57

5/8 93 145 150 209 209 225 240 100 92

¾ 150 234 250 350 350 370 395 146 124

7/8 202 372 378 550 550 591 629 -- 194

1 300 551 583 825 825 893 964 -- 390

1-1/8 474 872 922 1304 1304 1410 1523 -- 390

Chart 10

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SIZE METRIC CLASS 4.8

METRIC CLASS 8.8

METRIC CLASS 9.8

METRIC CLASS 10.9

METRIC CLASS 12.9

SOCKET HEAD 12.09

M6 4.5 8.5 12 14.5 M8 11 20 30 35

M10 21 40 60 60 M12 37 70 105 120 M14 60 110 165 190 M16 92 175 225 300 M18 125 250 350 410 M20 180 350 500 580 M22 250 475 675 800 M24 310 600 850 1000 M27 450 875 1250 1500 M30 625 1200 1700 2000 M33 850 1650 23050 2750

Chart 11

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1 0.7376 1 1.356 2 1.5 2 2.7 3 22 3 4.0 4 3.0 4 5.4 5 3.7 5 6.8 6 4.4 6 8.1 7 5.2 7 9.5 8 5.9 8 10.8 9 6.6 9 12.2 10 7.4 10 13.6 15 11.1 15 20.3 20 14.8 20 27.1 25 18.4 25 33.9 30 22.1 30 40.7 35 25.8 35 47.5 40 29.5 40 54.2

36.9 29.5 45 61.1 60 44.3 50 67.8 70 51.6 55 74.6 80 59.0 60 81.4 90 66.4 65 88.1

100 73.8 70 94.9 110 81.1 75 101.7 120 88.5 80 108.5 130 95.9 90 122.0 140 103.3 100 135.6 150 110.6 110 149.1 160 118.0 120 162.7 170 125.4 130 176.3 180 132.8 140 189.8 190 140.1 150 203.4 200 147.5 160 216.9 225 166.0 170 230.5 250 184.4 180 244.0

NEWTON METERS

(N-m) POUND-FEET

(LB.-FT.) POUND-FEET

(LB.-FT.) NEWTON METERS

(N-m)

Chart 12

NOTE: Tighten nylon insert lock nuts to approximately 50 percent of the value listed.

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(5) Wheel Mounting

Wheel mounting requires special purpose fasteners that resist the loads encountered in cornering, normal and tractive loads. Failure of wheel fasteners may usually be attributed to loss of preload, causing fatigue failure during operation of the vehicle. Loss of preload may be caused by inadequate torque due to nut reuse beyond the built-in safety factor of the fastener, corrosion, grease, dirt buildup or burrs. The threads of wheel fasteners should be clean and dry. No lubricants should be used when installing wheels to manufacturer’s torque specifications or when using an air wrench.

CAUTION: NEVER REUSE A WHEEL NUT MORE THAN FOUR TIMES.

(6) Threads

Thread fit is classified by the clearance existing between the threads of the bolt and nut. Class 3-A (bolt) and 3-B (nut) fit is; used in close-fitting applications where the fasteners are unplated. Class 2 threads are used on fasteners with placed threads. Class 1 threads are used on fasteners with hot-dipped threads.

B- TAPERED HUB BUSHINGS

The hub type is stamped on the hub itself and can be used to determine the corresponding torque value.

C- PIPE AND TUBE CONNECTIONS The primary purpose of a plumbing system is to conduct a fluid medium between system components. The conductors used in the refrigeration system are copper tubing and 45 degree SAE flare brass fittings. Pipe and pipe connections are classified by nominal size and wall thickness expressed as a schedule number. Schedule 40 pipe is standard. Tubing sizes refer to the outside diameter of the tube. Pipe connections are sealed by tapered threads that create an interference fit between the male and female fittings as the pipe are tightened. Dry seal pipe threads prevent seepage by full engagement of the thread roots to eliminate annular clearance. Prope

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(1) Flare Fittings

The 37 degree flare fitting seals a tube connection by compressing the flared end of the hose coupling against the end of a mating fitting as the coupling nut is tightened. Alternate installations seal a connection using a flared tube, a supporting sleeve and compression nut. Standard forged or extruded 45 degree flare fittings are used to seal automotive and refrigeration tubing connections.

(2) Straight Thread O-Ring Fittings

Straight thread fittings are frequently used for hydraulic system connections. They are ideal for high pressure use since the seal becomes tighter as pressure increases.

(3) Hose Fittings

Hose fittings are essentially the same as tube fittings. The hydraulic hose fittings used on the unit incorporate reusable screw-on swivel connectors. The feature eliminates twisting the hose during installation.

(4) Four-Bolt Flange Fittings

Flange fittings allow effective assembly and joining of larger diameter tubing. Tube fittings for large diameter tubing would require very large hexagon wrench surfaces and could not be adequately torqued. Flange fittings simplify assembly procedures. The fittings are sealed by an o-ring or other packing to prevent pressure leaks. Split flange fittings comprise four elements; a flanged member connected permanently to a tube, tubing assembly, and o-ring installed in a machined groove in the end face of the flange, and two mating clamp halves with appropriately sized bolts that connect the split assembly to a mating surface. Mating surfaces must be cleaned, honed, and polished to a 32-microinch finish to assure a leak-free connection. Joints will develop leaks if surface imperfections are present. (a) Installation

(1) Clean the surface to be sealed. Hone and polish the surface as required.

(2) Install the o-ring and back up washer, when used, into the

groove using petroleum jelly to hold it in place. (3) Assemble the split flange halves loosely, making sure that the

split is centered and perpendicular to the port, Hand-tighten the cap screws to hold the parts in lace. Do not pinch the o-ring.

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(4) When assembling single flange connections, place the hydraulic line in the center of the flange and install the cap screws. The flange must be centered on the port. Hand-tighten the cap screws to hold the flange in place. Do not pinch the o-ring.

(5) Tighten the retaining screws evenly in a criss-cross pattern.

CAUTION: DO NOT TIGHTEN FASTENERS USING AN AIR WRENCH. DO NOT TIGHTEN ONE SCREW FULLY BEFORE TIGHTENING THE OTHERS. DO NOT OVERTIGHTEN THE FASTENERS.

5- STRUCTURAL REPAIRS

A- FRAME REPAIR

CAUTION: TO AVOID REDUCING FRAME STRENGTH, DO NOT DRILL HOLES IN THE MAIN FRAME STRUCTURE. (1) Drilling Precautions

If a hole must be drilled in the main frame, follow the guidelines provided below:

(a) Do not locate the holes closer than one inch (25.4 mm) to the edge

of an adjoining hole. (b) Do not locate the hole closer than one inch to the edge of a flange. (c) Do not locate the hole adjacent to any other existing brackets or

components of the frame. (2) Frame Straightening

Damaged frame members can be repaired by straightening and rewelding. To prevent internal stresses in the metal, straighten only structural members that are not severely bent. Replace severely deformed members.

CAUTION: IF HEAT IS REQUIRED TO STRAIGHTEN A FRAME MEMBER, KEEP THE TEMPERATURE BELOW 1,200ºF (649ºC) (A DULL RED GLOW) TO PREVENT WEAKENING THE METAL IN THE FRAME MEMBERS AND CAUSING PERMANENT DAMAGE.

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NOTE: If cracks develop during the straightening procedure, reweld, and reinforce the cracked material.

(3) Welding Procedure

CAUTION: DISCONNECT THE BATTERY GROUND CABLE BEFORE USING ANY ELECTRIC WELDING EQUIPMENT.

NOTE: All welding on the frame must be done with electric welding equipment. The heat should be kept to as small an area as possible to prevent a change in metal hardness.

Proceed as follows to repair a crack in the frame:

(a) Prepare the crack before welding a reinforcement over the

cracked frame member by wire brushing the area around the crack to remove paint, grease, and to completely expose the crack and assure good weld adhesion.

(b) To stop the crack from spreading, dill a ¼ inch (6.35 mm) hole

at a point 0.50 inch (12 mm) beyond the root of the crack. (c) Grind out the full length of the crack to the hole to form a v-

shaped slot with the base of the “V” contacting the reinforcement.

(d) The base of the “V” should have at least .06 inch (1.52mm)

opening to ensure weld penetration to the reinforcement when welding the crack.

(e) Clean the surface of the frame under and around the

reinforcement. (f) Clamp the reinforcement securely to the frame prior to

welding. (g) Weld the reinforcement all around after welding the crack “V”

to the reinforcement. (h) To prevent corrosion, clean the area and apply an approved

primer. Repaint the repaired area.

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B- SHEET METAL REPAIR

NOTE: Complete all welded repairs before preparing the equipment for painting. Paint is quickly scuffed off sharp dents leaving metal exposed to rusting and corrosion. Damaged sheet metal, therefore, should be repaired as soon as possible. Force damaged panels outward in the direction opposite the force which caused the damage in order to relieve metal stress. Use a back-up tool under the hammer when bumping a panel to achieve a smooth surface. (1) Surface Preparation

(a) Base Metal

(1) Remove all traces of loose rust, oil, grease, wax, or foreign material from the bare metal surface using a chemical cleaner, sandblasting, scraping, wire brushing, sand paper, or steel wool.

(2) Treat bare aluminum or steel metal surfaces with an approved

metal container. Clean and dry the metal. (3) Apply an acrylic chromate primer to the exposed metal surface

immediately after cleaning. (4) Scuff sand the primer with #180 grit sandpaper being careful

not to sand through the primer. (5) Using a clean, lint-free cloth and solvent, wipe the area to be

coated with an approved prepaint cleaner and allow it to flash off.

(b) Previously Painted Surfaces

If the surfaces are in good condition, only sanding will be required. Sand and featheredge all chipped paint with a #320 grit sandpaper.

NOTE: Wet sanding will reduce the amount of surface scratching.

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(1) Wipe the sanded surfaces with an approved prepaint cleaning

solvent and allow it to flash off. (2) If the existing finish is in poor condition, remove it by

sandblasting or with a chemical paint stripper.

NOTE: On equipment previously coated with acrylic enamel, a complete coat of primer-sealer is not necessary. Prime and seal only the exposed metal surfaces. Scuff sand the weathered enamel.

6- CLEANING AND PAINTING

A- CLEANING

Equipment subjected to airborne pollen, insect and bird droppings, or other organic matter, especially equipment subjected to these materials that is exposed to high temperatures and sunshine should be washed as often as necessary to keep them clean and free of organic matter and industrial chemical fallout. Failure to do so may result in damage to the surface finish. Wash the exterior of the unit using an approved wash concentrate. Dilute the concentrate to the required strength following the manufacturer’s instruction. Rinse with clean, cold water. Do not wash the unit with hot water, in direct sunlight, or while the sheet metal is hot.

WARNING: SOLVENT MAY AFFECT SKIN, EYES, AND RESPIRATORY TRACT. USE ONLY IN A WELL-VENTILATED AREA. AVOID PROLONGED BREATHING OF VAPORS. AVOID EYE AND REPEATED SKIN CONTACT. KEEP AWAY FROM SPARKS AND FLAME. TO AVOID POSSIBLE PERSONAL INJURY, NEVER EXCEED 30 PSI (207 kPa) AIR PRESSURE FOR CLEANING OR DRYING PURPOSES. USE NIOSH APPROVED EYE PROTECTION WITH SIDE GUARDS TO PREVENT EYE INJURY FROM FLYING CHIPS. USE ONLY APPROVED NOZZLES ON AIR HOSES. Prope

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CAUTION: NEVER USE STEEL WOOL, ABRASIVE CLEANERS, OR STRONG DETERGENTS CONTAINING HIGHLY ALKALINE OR CAUSTIC MATERIALS TO CLEAN THE SURFACE FINISH. NEVER IMMERSE ELECTRICAL COMPONENTS, PACKINGS, OR RUBBER, PLASTIC, OR TEFLON PARTS IN DRY-CLEANING SOLVENT. WIPE PARTS WITH A CLEAN, LINT-FREE CLOTH. DRY CLEANING SOLVENT CAN REACT WITH MATERIALS AND RESULT IN SEVERE DAMAGE OR DESTRUCTION OF PARTS.

NOTE: The surface finish should be washed frequently. Never wipe painted surfaces with a dry cloth. This practice rubs in surface dust and dirt, scratching the finish like sandpaper. (1) Clean parts in a tank or spray booth using dry-cleaning solvent. (2) Wash cleaned parts by flushing or spraying. When necessary, use a soft

bristle, non-metallic brush moistened in dry-cleaning solvent. (3) Except for bearings, dry parts using compressed air after cleaning. (4) Unless specifically called for in maintenance procedures, do not use metal

scrapers, wire brushed, abrasive wheels, or abrasive compounds when cleaning parts.

(5) Clean electrical parts such as relays or switches with a lint-free cloth

moistened with dry cleaning solvent. (6) Clean the exteriors surface of the battery with a steam cleaner or with a

pressure washer and soap solution. Do not use a cleaner that will attack aluminum or copper.

(7) Wash painted surfaces of the unit with a solution of ¼ pound of soap chips

to one gallon of water. Rinse with clean water and dry with a lint-free cloth or allow to air dry.

(8) Remove nicks, burrs or scratches from surfaces in contact with gaskets,

packings, or seals using a fine file or medium grit emery cloth.

NOTE: Do not alter the shape of the part by removing too much material. Wet sanding will reduce the amount of surface scratching.

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(9) Replace hoses with broken or frayed fabric cover, damaged fitting threads, breaks or leaks.

(a) Wipe the sanded surfaces with an approved preprint cleaning solvent

and allow it to flash off. (10) If the existing finish is in poor condition, remove it be sandblasting or with

a chemical paint stripper.

NOTE: On equipment previously coated with acrylic enamel, a complete coat of primer-sealer is not necessary. Prime and seal only the exposed metal surface. Scuff sand the weathered enamel.

B- PAINTING

(1) Masking the Equipment

(a) Install suitable covers over the wheels. (b) Mask off components and door openings as required.

NOTE: For spraying primer and topcoat, the lowest pressure that provides a full fan or spray pattern at the gun usually presents the best appearance. During hot weather or high humidity, small amount of retarder will maintain a wet film and obtain maximum flow. To avoid slow drying, avoid excessive use of retarder.

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WARNING: ACRYLIC ENAMEL IS A CLASS 1, EXTREMELY FLAMMABLE MATERIAL. MANY PAINT REPAIR SYSTEMS CONTAIN HARMFUL ADDITIVES. OBSERVE ALL RECOMMENDATIONS AND WARNINGS LISTED ON THE CONTAINER FOR THE MATERIALS LISTED ON THE CONTAINER FOR THE MATERIALS SELECTED. PERSONNEL WITH RESPIRATORY PROBLEMS OR ALLERGIES SHOULD AVOID EXPOSURE TO THE VAPOR/SPRAY MIST. VAPOR AND MIST SPRAY CAN BE HARMFUL. THESE MATERIALS SHOULD BE APPLIED ONLY IN AN APPROVED PAINT SPRAY BOOTH WITH ADEQUATE RESPIRATORY PROTECTION. THE RECOMMENDED PROTECTION IS A NIOSH APPROVED POSITIVE PRESSURE AIR SUPPLY RESPIRATOR. RESPIRATOR PROTECTION IS RECOMMENDED FOR USE DURING THE ENTIRE SPRAYING TIME AND UNTIL ALL VAPOR AND MISTS HAVE DISSIPATED. FOLLOW THE USAGE INSTRUCTIONS PROVIDED BY THE RESPIRATOR MANUFACTURER.

(2) Spray Coating Procedure

(a) Reduce the topcoat acrylic enamel following the paint manufacturer’s instructions.

(b) Apply a wet, sag-free coat. Allow 10 to 15 minutes flash off time.

Apply a second and third wet, sag-free coat and allow it 10 to 15 minutes flash-off time. Apply a final, wet sag-free coat. Allow 10 to 15 minutes flash-off time.

(c) Immediately clean the spray equipment using multipurpose paint

precleaner. (d) Allow at least two hours drying time at 70°F (21°C).

NOTE: Acrylic enamels provide good color retention and durability. They resist UV light, water, oils, alkalines, and acids.

CAUTION: ACRYLIC ENAMELS DO NOT RESIST HYDRAULIC FLUIDS SUCH AS SKYDROL OR TURBINE OIL.

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