Engine Lubricants and

Lubricating Systems

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Functions of Engine Oils

1. Reduce wear

2. Reduce friction

3. Seal Compression

4. Reduce noise

5. Cool engine parts

6. Reduce rust

7. Keep parts clean

Organizations Providing Uniform Standards for Oil S.A.E.

Society of Automotive Engineers A.P.I.

American Petroleum Institute A.S.T.M.

American Society of Testing & Materials American Automobile Manufacturers

Association Engine Manufacturers Association I.S.O.

International Standards Organizations

Properties of Motor Oils

ViscosityViscosity Index (VI)Flash PointPour PointPer cent sulfated ashPer cent zinc.

Properties of Motor Oils

ViscosityViscosity Index (VI)Flash PointPour PointPer cent sulfated ashPer cent zinc.

Viscosity Measure of the "flowability“

Kinematic Dynamic

Property – Resistance to flow Shearing stress

High viscosity - thick oils Too high viscosity may not reach all parts

Low viscosity – thin oil Too low viscosity may not provide enough strength to

keep parts from wearing

Dynamic & KinematicViscosity

Kinematic Viscosity Measurement

Saybolt Viscometer Glass capillary viscometers

Dynamic Viscosity Measurement

Typical Brookfield Viscometer

Weight of oils Common term identifying viscosity for oils Numbers assigned by the S.A.E.

correspond to "real" viscosity, as measured by accepted techniques.

These measurements are taken at specific temperatures.

Oils that fall into a certain range are designated 5, 10, 20, 30, 40, 50 by the S.A.E.

The W means the oil meets specifications for viscosity at 0 F and is therefore suitable for Winter use.

_______________________________________________________________

| |

| SAE Gear Viscosity Number |

| ________________________________________________________ |

| |75W |80W |85W| 90 | 140 | |

| |____|_____|___|______________|________________________| |

|

| SAE Crank Case Viscosity Number |

| ____________________________ |

| |10| 20 | 30 | 40 | 50 | |

| |__|_____|____|_____|______| |

______________________________________________________________

2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42

viscosity cSt @ 100 degrees C

Properties of Motor Oils

ViscosityViscosity Index (VI)Flash PointPour PointPer cent sulfated ashPer cent zinc.

Viscosity index The measure of an oil's ability to resist

changes in viscosity when subjected to changes in temperature.

As temperature increases

viscosity decreases. Low temperatures –

High viscosity High temperature –

Low viscosity

Multi-viscosity/Multi-grade Oil Oil meeting SAE requirements for

both low-temperature requirements of light oil and high-temperature requirements. Also know as multiweight oil.

Oil that meets certain low-temperature and high-temperature requirements simultaneously

(e.g., SAE l0W-40).

Properties of Motor Oils

Viscosity Viscosity Index (VI)

Flash Point Minimum sample temperature at which vapor is

produced at a sufficient rate to yield a combustible mixture.

Pour Point The lowest temperature at which oil will pour.

Per cent sulfated ash Per cent zinc.

Properties of Motor Oils

Viscosity Viscosity Index (VI) Flash Point Pour Point

Percent sulfated ash how much solid material is left when the oil burns. A high ash content will tend to form more sludge

and deposits in the engine. Low ash content also seems to promote long valve

life. Look for oils with a low ash content. Per cent zinc.

Properties of Motor Oils Viscosity Viscosity Index (VI) Flash Point Pour Point Per cent sulfated ash

Percent zinc the amount of zinc used as an extreme pressure,

anti-wear additive. The zinc is only used when there is actual metal to

metal contact in the engine. Hopefully the oil will do its job and this will rarely occur, but if it does, the zinc compounds react with the metal to prevent scuffing and wear.

A level of 0.11% is enough to protect an automobile engine for the extended oil drain interval, under normal use.

Common motor oil additivesViscosity index improvers

used to enhance the base qualities of the oil, and to keep the oil from thinning too much as heat increases.

Pour-point depressants prevent crystals from forming in extreme

cold conditions, and consequently lower the oil's pour point (temperature at which it pours).

Common motor oil additivesOxidation inhibitors

help prevent the oil from oxidizing (in other words, burning). When oil oxidizes, it loses its ability to protect the engine. It also produces sludge deposits and traps corrosive acids.

Rust-corrosion inhibitors help prevent and neutralize water and

oxygen from acid-etching the metals in the engine and forming rust particles. If this corrosion were to happen, some complex acids would form and other sludge problems would occur.

Common motor oil additivesDispersants

help the oil to absorb and retain contaminants such as dirt or tiny metal particles (from engine wear) until the oil passes through the oil filter, where the contaminants are trapped.

Detergents help to remove contaminants from the engine

components and hold them in the oil until it reaches a filter, or until it is changed the next time. They don't only clean up a dirty engine.

Common motor oil additivesFriction modifiers/wear inhibitors

"stick" to engine surfaces better, reducing friction and improving fuel economy. Oils with the "energy conserving" labels contain friction modifiers.

Foam inhibitors (Antifoamants) prevent the oil from being whipped into many

tiny air bubbles. Air bubbles don't lubricate. This also helps prevent sludge formation when the emulsion process is a possible threat in an engine.

Types of Motor Oils Petroleum Based

Refined from crude oil Supplemented with additives

Synthetic Lubricants chemically engineered from pure chemicals

rather than refined from crude oil. Can provide significant advantages over refined oils.

Longer oil change intervals Longer engine life Increase gas mileage

More expensive

What the h___ is he talking about?

Items that tell us about selecting an oil!

What the h___ is he talking about?

How to select an oil for different purposes.

What to look for on an oil container.

What Oil Should You Use

API “Donut”

GasolineServiceClassification

DieselEngineClassification

Lubrication SystemsSplash

Dipper Slinger

Force Feed & SplashFull Force Feed

Splash Lubrication

Force Feed and Splash

Full Force Feed

Oil Pump

Oil pump intake screen

Engine Oil Degradation and Contamination Oil thickening

Oxidation Vaporization of lighter

components Fuel

Hydrocarbon compounds Combustion Products

Carbon Water Sulphur Oxides Fuel chemical additives

Dust and Dirt Metal – from wear of

components

Oil Filtration Systems

By-PassFull –FlowShunt

Engine Lubrication System with both by-pass and full-flow filtration

Two filters provide ability to filter smaller particles

Filter elements Surface

Pleated paper Metal screen

Depth Cotton waste

Changing oil and filters renews engine protection Dirty oil reduces life of an engine. Reduce maintenance and increase engine life

by changing engine oil and filters on a regularly scheduled basis.

Interval between changes depends on operating conditions.

Oil analysis provides management of oil change intervals Recommend for fleet operations.

Oil Pressure – Important Sensor

Low pressure light indicator

Lubrication Links on the Web Motor oils and more Motor Oil Functions & Properties Selecting motor oils

API Starburst and Donut Motor Oil Additives Lubrication Systems Filtration Systems

Sources of oil contaminants Filters & filter media

Synthetic oil base stocks Synthetic oil history Oil Analysis –

Example 1 Example 2