Thread: 300tdi injector pump "bleeding"

From the manwell, I have been reading it seems I dont have to disassemble the whole front end to get the injection pump off. I just need LRover special Tool LRT-12-045. Assuming I need to swap pumps over I will be going to make up said tool... would anyone have a photo or diagram of the back of said tool as it fits into the front timing cover???? The outside face seems to have holes for the gear retaining bolts, Im guessing the inside face is machined to the inspection whole so that the pump gear is held in place without disrupting the t-belt... sorry for the ramble Im just happy I dont have to pull the front end down again

Steve

excerpt from manual below:

6. Remove injection pump access plate, complete
with gasket, from front cover plate.
7. Fit pin from LRT-12-045 to injection pump gear.
8. Restrain pulley nut to prevent straining timing
belt and remove drive gear to pump hub fixing
bolts and retaining plate.
9. Remove pin from pump gear.
10. Fit gear retaining tool LRT-12-045 with an 8 mm
washer, 1,5 - 2 mm thick, under each bolt head
in addition to the existing washer.

from memory there is a small adjusting screw that is buried by a cover bolt/nut arrangement if you pull the cover bolt/nut off that will allow the fuel pump to more easily bleed without all the naffing around with the filters and everything else.

Have you proven that you are getting fuel from the lift pump to the injector pump at at least (OOMA) 4 psi?

there is a small pump and shuttle valve on the bottom of the pump body that pressurises the pump body and it has the potential to , if left sitting with fuel in it thats gone off, clag itself.

Ive not seen one do it on a tdi but I have seen an old series diesel do it and its basically the same pump.

In theory once you get fuel to the base of the injecot pump its internal pump should take over and then everything is apples but if the shuttle valve is stuck closed (where it would be immediately after shut down) and the internal pump has a stuck vane then you wont get fuel into the pump unless you develop enough pressure to overcome the check valve (which is part of the shuttle valve). If the check vavle is stuck you might try a light blast of compressed air on the inlet side.

It is a very real possibility that the lift pump may be connected in reverse. don't laugh, I did it once. (Note the word ONCE)
This actually has the effect of sucking the fuel from the injector pump!!

Pull the lift pump pipes off and crank the engine. Find the sucking port and plug the 'in' line to that from the tank.

JC

I thought they had differnt size fittings and arrows on them.....

Originally Posted by Blknight.aus

I thought they had differnt size fittings and arrows on them.....

Nope. Same fittings, and unless an aftermarket lift pump has been fitted with arrows on it (Some have, some don't) then it can happen...

JC

thanks for the heads up guys,
will check the lift pump plumbing and then maybe a shot of air down the intake...

had a scrounge around after dinner tonight, with not too much naffing around it wont be too hard to knock up a jig to hold the pump gear in situ to allow a pump change out... i guess thats the best option if above two fail.

thanks again.

Steve

thanks Justin and Blknight... took about an hour to sort the problem.

lift pump was plumbed correctly but was supplying insufficient pressure to feed the IP. Swapped in a good lift pump and then bled the lines and the old girl roared into life!!!!

But of course... if only it was so simple. The IP is leaking like a bloody sieve.
Sitting idle has obviously been bad for its seals!!! The main leak seems to be coming from where the govenor assembly bolts to the pump body. So I will be having an espresso, then heading back to build a pump holding jig and swapping the pumps over anyway

At least the wind is blowing 30 knots and so its not like I could be out at the reef anyways???

thanks again guys

Steve