Lift pump failure?

Hi there

Ive been suspect of lift pump failure for a while on my 1995 300tdi after asking around. Found the power was limited in anything but the perfect gear.

Anyway, pulled the wire off the fuel pump earlier, got someone to crank the engine while i opened the bleed screw on the fuel filter housing. No diesel was present at all, not even the slightest drop.

Does this mean my lift pump has failed?

Thanks

If you pulled the wire off then the fuel cut off switch was not open so I don't think any diesel would be coming thru. Loosen the four injector pipes so she wont start, leave the wire on and try again....

blimp said:

If you pulled the wire off then the fuel cut off switch was not open so I don't think any diesel would be coming thru. Loosen the four injector pipes so she wont start, leave the wire on and try again....

Click to expand...

Ahh thats interesting. I was advised by people on here to do what i did.

Doesnt the lift pump run off the cam or crankshaft (not sure which) and therefor doesnt involve any electrics?

Sorry misread, thought you'd opened a screw on the pump. But if you opened the one on the filter and the pump is after the filter you'll only be sucking air thru the filter bleed screw.

Best thing to do is disconnect the delivery pipe at the injector pump. Hold your finger over the end of it and crank the motor and see what pressure you have, should be more than enough to blow past your finger with reasonable pressure...

Have you got a hand priming lever on your lift pump? If so make sure the cam lobe for the lift pump is away from the lever....(roll the Landy backwards and forwards in gear till the lever feels like it's doing something).... Then undo the bleed screw on the fuel filter. When you pump the hand lever this will squirt diesel out of the bleed screw. I would have expected what you did above cranking the engine with the bleed screw open would have done the same. If it doesn't pump fuel, the lift pump is broken, or it's run out of fuel, or there is a air leak between the tank and the lift pump, or possibly the fuel pickup is clogged up.

It sounds like you are doing the right thing to me in the first place.

Cheers guys.

When i bought the land rover, i noticed that the lift pump was flicking away with the engine revs. Did some research and found out it clips up to stop it from flicking with revs.

So the lever still remains clicked up and secure when i tested it. I'll do as you suggest though and see if it makes any difference.
Maybe securing the lever ive disengaged it??

the lever just operates the cam lever, theres no "disconnection" on it, it just stows to stop it flapping about.
I tested mine by disconnection the lift pups output, and the fuel pump solenoid and getting someone to give it a crank.
300tdis seem to vary betweeen they wont go above tickover to down on power to lost top end oomph when the pumps go. mine just looses its top end and wont rev highly, my mates wont drive, and will only manage tickover :/

timtheenchanteruk said:

the lever just operates the cam lever, theres no "disconnection" on it, it just stows to stop it flapping about.
I tested mine by disconnection the lift pups output, and the fuel pump solenoid and getting someone to give it a crank.
300tdis seem to vary betweeen they wont go above tickover to down on power to lost top end oomph when the pumps go. mine just looses its top end and wont rev highly, my mates wont drive, and will only manage tickover :/

Click to expand...

Thanks very much. I'll give that ago later and see if any diesel is present.

Mine seems to have little top end. Struggles over 50/60 And anything but the perfect gear makes the engine labour. Could be just me, but going to check anyway

Whats the best way of disconnecting the output to test it? Undoing the input banjo on the fuel filter? Worried about re sealing though

Took the outlet from the lift pump off (inlet to fuel filter banjo) checked for a flow out of the pipe, and to my surprise there was a flow of diesel out the pipe. Thanks for your help guys