Thread: Swapping Injector Pumps

before you do that, hve you got enough fuel pressure coming out of the lift pump to the injector pump? checkk for a blocked fuel feed fro mthe tank or blocked filter.

Thanks for the suggestion but based on investigations to date this is unlikely.

The FIP is the only thing left.

The knock is only at idle and low rpm. It clears as the rpm rises (i.e. as the timing becomes more advanced).

The D'Fer was dyno tuned by the previous owner and I suspect that the timing is a fraction too advanced. Theoretically this is great for high rpm operation, but I'm more interested in reliability and longevity than revving the ring off the truck.

Regards,

Mathew

Originally Posted by SavingTheDefender

Thanks for the suggestion but based on investigations to date this is unlikely.

The FIP is the only thing left.

The knock is only at idle and low rpm. It clears as the rpm rises (i.e. as the timing becomes more advanced).

The D'Fer was dyno tuned by the previous owner and I suspect that the timing is a fraction too advanced. Theoretically this is great for high rpm operation, but I'm more interested in reliability and longevity than revving the ring off the truck.

Regards,

Mathew

I wouldn't say that....

if the mechanical pump is struggling to make enough effective flow at low RPM but upping the RPMS gives it enough flow to get the correct operating pressure to the FIP...

I get this quite frequently when I screw up my WVO mix and the engine bay filter is still cold

I'll take your advice and order a lift pump. Not much point me asking for advice and not being prepared to take it!

The quest continues...

Regards,

Mathew

And she's still knocking...

Worth the effort and occasional swear word to swap it over. Manually pumping the old one produced, well nothing. The new one gave a distinctive puff of air and positive action when testing dry.

I turned down the idle while I was there, but The D'Fer is still knocking when cold. Less so when warm.

Any other suggestions out there?

Thanks,

Mathew

I know you changed the injectors did you pattern them?

and have you checked the injector sealing?

I know you changed the injectors did you pattern them?

are you getting a good return from the inector spill lines?


and have you checked the injectors sealing in the head?

I replaced #3 injector with a new one following the advice of a 'specialist' and swapped the other three injectors with those from my 300tdi Discovery, which runs as quiet as a church mouse.

I've not yet put the injectors from The D'Fer into the Discovery to cross check, as I was planning on sending them to my local diesel center for a clean and test etc.

Having turned down the idle The D'Fer is similarly quiet at idle, except for the bloody knock!

Some questions:

1. Apart from changing the return lines to clear plastic, how to you check the return flow?

2. How do you 'pattern' a diesel injector? I'm working on the basis at the moment that given that the injectors are either new or came from a reliable source all is well in that regard.

I replaced the copper injector washer/seal for new on each injector. No air leaks.

Regards,

Mathew