Discovery TD5 Injector replacement guide

Parts required:

ERR7094 – ROCKER GASKETT - £14.41 + VATERR7004 – INJECTOR ‘0-RING’ – ABOUT £5ERR6417 – INJECTOR COPPER WASHER – ABOUT £4

First, ensure your replacement injector has had a new o-ring and copper washer fitted.Remove the battery cover, and disconnect the Negative lead of the battery. Remember to remove yourkeys from inside the car first!!!

Remove the accustic cover from the top of the engine, secured by three 13mm bolts.Remove the viscous fan top cover, secured by four phillips screw fastenings.To remove the viscous fan, i removed one of the three 10mm bolts from the fan pulley, to allow me roomto get a large adjustable spanner on the fan fixing nut. Strike your spanner with a hammer, so as to turnthe fan in an anti-clockwise direction. This shock should release the fan, and allow it to spin off on it's

threads.

Disconnect the quick release fuel hose connectors from the fuel connector block on the cylinder headand fuel cooler, to drain fuel from the head.

Remove the rocker cover breather hose, and tie it back out of the way.With a 10mm socket, undo and remove all of the rocker cover fixing bolts.

Carefully lift the rocker cover up, and to the left, whilst keeping it horizontal, to remove it.Remove the five electrical connectors to each injector and put to one side.

At this point, using a 24mm socket on the crankshaft pulley, turn the engine in a clockwise direction, and

observe the numbers marked on the timing chain sprocket. You will see a right angle on the cam carrierhousing. Line up a number marker (i started with 3, because it's in the middle) on the timing sprocket.

Now No.3 cylinder's injector will now be at full compression.

Locate the five injector adjustment screws on the rocker shaft. Undo each locking nut using a 13mm ringspanner, and turn the adjusting screw fully anti-clockwise until all pressure has been released from the

injector spring. Lock off the screw to hold it in place. Repeat for all injectors.Using a 3/8" socket on a ratchet, undo all the rocker shaft bolts. Remove the rocker shaft.

Using a 10mm socket, undo the injector retaining clamp bolt, and remove the clamp.

To remove the injector, i borrowed the slide hammer designed for the job from my local Land Rover

dealers (Duckworth Landrover). Tool part number is: LRT-12-154/1. Place this over the injector body &spring, do up the jubilee clip. The injector should pop out in three pulls.

If the injector you removed was a good one, put it straight into a clean plastic bag, and seal it up toavoid any contamination entering the injector.Now it is VERY IMPORTANT to remove any fuel that may have fallen into the combustion chamber,

through the injector nozzle hole. I used a length of windscreen washer hose, connected to a syringe. Imanaged to pull out about 30-40ml of diesel! If left in, this could have caused severe engine damage!Once i was satisfied i'd removed nearly all the diesel, i disconnected the washer hose from the syringe,

and attached it the the hose on a vax, with a bit of duck tape. This is now a precision suction tool, idealfor sucking out any bits of muck in the injector recess. Sounds rough, but works a treat!!!

Take your replacement injector out of it's bag, and offer it in place. I pushed it down to a snug fit, andthen using the closed slide hammer, knocked the injector base down, to push it all the way home.

Now refit the injector retaining clamp, ensuring it's located on it's dowel, and using a 10mm socket,tighten it to a torque of 32Nm.Put a drop of clean engine oil on the rocker socket, on top of the injector.

Offer the rocker shaft back into position, and losely fit the rocker retaining bolts with a 3/8" socket.Find which injector should be fully compressed, and start progressively tightening the rocker bolts fromaround this location. Tighten all rocker bolts to a torque of 33Nm.Using your 24mm socket and ratchet, turn the engine to line up an injector number on the timing chain

sprocket.Undo the adjustment screw locknut for the appropriate injector, and then using a flat blade screwdriver,turn the adjustment screw clockwise to compress the injector. When the injector plunger had bottomed

out (so you can no longer tighten the adjustment screw), turn the screw back, 1 full turn and then lock inplace with the locknut. This should have a torque of 16Nm.Now turn the engine clockwise using your 24mm socket and ratchet, until the next injector number is

lined up on the timing sprocket. Repeat adjustment sequence as above for all remaining injectors.When all injectors have been set, turn the engine clockwise, two complete rotations, to ensure none ofthe injector plungers bottom out. If you followed the above correctly, all should be well. Incorrectly

adjusted injectors will almost certainly cause damage!!!Replace the injector electrical connectors.Fit a new gasket to the rocker cover. Part number ERR7094.Replace the rocker cover, taking care to ensure the semi-circular part to the back, is properly located.

Refit and tighten all rocker cover bolts.Refit the breather hose to the rocker cover.

Refit viscous fan by offering up, and spinning on in a clockwise direction. I used a large adjustablespanner and a hammer to drive it home tightly.

Reconect the quick release fuel hoses, to the fuel connector block on the cylinder head.Refit rocker accoustic cover, and viscous fan cover.Reconnect the battery Negative lead, and then start the fuel purging sequence.

Once completed, the engine should fire up straight away!