Cant get delphi lift pump to prime.

This defender has issues that may, or may not be fuel related.

In the interest of doing the simple things first, i swapped the lift pump this morning.

Can i get any action out of the new one? Nope...

Ive got the filter off as well, so as to see when the fuel is coming up, but i just cant get any action out of it.
The manual lever (delphi oem) has no real tension. Im sure the pump on our 300tdi disco is loose all the way when its on the cam, but, when off the cam, its loose, then hard, depending, i guess, on the cam position.

This one is just loose all the way - ive pulsed the starter, ive turned it over for some seconds, and nothing makes a difference.

I took the top off and poured some diesel in too, but still nothing.


Now i seem to remember, when i changed the disco one, some time back, that it might have been similar, before it primed? I seem to recall having issues with the olives sealing, and, when it was sucking in air, there was no tension on the manual lever. I dont know if im remembering this right though?



The olives on this one, im pretty certain, will be sealed, but im now wondering if the issues the motor was having (which im loath to type here, as its already turning into some thesis!) may be air leak on the line between the tank and the lift pump?


What do you think?

Lift pump connected correctly?If so take off pipes and see if you can feel vacuum pumping lift pump manually-on 300 tdi lower pipe goes to tank

Cheap Delphi pump off ebay ?

I learnt the hard way they are fakes or rebadged crap.

Absolutely not delphi- thats why they are half the price.

Same symptoms as you.

biolandy said:

Lift pump connected correctly?If so take off pipes and see if you can feel vacuum pumping lift pump manually-on 300 tdi lower pipe goes to tank

Click to expand...

Like biolandy says, take the pipe off or even the whole pump and put your thumb over the inlet, it should suck really well when you manually work the primer.
I had a cheapy eBay one that worked on the bench but wouldn't on the engine, did my head in for a bit but when I held the new pump next to the old I could see that the arm which sits on the camshaft was manufactured wrong and didn't sit on the cam properly.
It was quite a heavy steel 'U' section and impossible to bend that's why I knew it was a manufacturing fault rather than transit damage.

Have you had the lid off? Theres a tit that needs to line up right.
Also try wind it over with a spanner as sods law you would crank it over a bit and end up with the lift pump sat on the cam again.

Hand prime won't work if the pump is on cam.