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waorth
09-24-2008, 09:18
Hi to all,

after about 200mls of highway driving my engine suddenly stopped. I found out that no fuel does go to the injectors. Fuel is present before and after the filter (Stanadyne 80 type). Long time ago i installed a electric pump for filter change purposes, so priming is not a problem.
Seems that my ip (4 year old DB 4911) is the problem.
From many of the older posts here i doubt that the pump is completely dead. It failed extreme suddenly. I felt a very light tip at the throttle (like when installing the fast idle solenoid) and then after releasing the throttle the engine died - no stutter at all.

The electric shutdown solenoid for sure does work. With the pump still in the vehicle i opened the top cover (checked solenoid again) and siphoned off the fuel. In comparism with my old pump nearby, i cannot not see any fault or broken part.
However if i try to pump diesel into the (still open) upper part of the pump, it seems to go very slow - definately a lot slower than the fuel comes off the filter outlet. Is this normal because it is the return cycle?

Could it be a broken gear drive blocking the pump internally?

Are there any other ways to test the pump in the vehicle?

Any help is highly appreciated.

Thanks in advance.

Walter

waorth
10-03-2008, 05:25
Update 10/3/08

Disassembeled the pump and opened it.

What I found is this:

http://up.picr.de/1364100.jpg


I get another shaft with which I tried to turn the pump - without success. So it seems that the 4911 is definately shot.

I'm already in contact with usdieselparts.com for a new pump - hopefully they'll not only accept wire transfer (=bad) with international customers.

Walter

john8662
10-14-2008, 21:21
Great troubleshooting!

Yeah, when the head/rotor seizes, this is what happens, a lot better than the pump trying to turn on the mounting flange on the timing cover for sure.

The head for the 4911 ain't cheap either, best finding another pump (which is what you're doing it looks like).

J