(2001)Have just had my VP44 injector pump replaced 12/07/09. Went out on the road, had no option but to take to dealer. Cost me $2800 for a factory rebuild. Problem is now the fuel keep draining out of the filter housing after sitting for several hours and it difficult to crank or just cuts off with me when out driving. Had to have it towed to a dealer here at home yesterday. Dealer trying to tell me it was just out of fuel, that the gauge is off, still show 1/4 of a tank. They put in 4 gal and it cranked for them. So I go to pick it up, but first take the cap off the filter housing and sure as I expected there's no fuel there.
They try telling me it's running back through my lift pump, but this is not right because it fills from the top and drains from the bottom to the injector pump.
To me it seems like it's draining through the injector pump return line back to the tank. I told them to keep for another day or so and drive it to be sure.
Any ideas or suggestion would be appreciated.

 

If you park downhill and it starts normally, it is a indication of leak on the return side.If air is trapped in filter it will drain back through suction line and be a pain to get started. I loosen the filter cover and put in bump mode. When solid fuel escapes from threads of filter, I tighten the cover down. It this point if IP has lost prime, I loosen a couple injection lines and crank till sprays fuel. Tighten and will generally start almost immediatelly. Any air leaks in suction side will also cause. Remember air will leak in easier than fuel will leak out..

 

If it's leaking on the return side and it's not leaking on the ground but back to the tank, were is it leaking? Would it not have to flow through the IP to get back to the tank? And the most curious thing is that I took the lid off and ran the lift pump until the bowl was full then cut it off. Let it set over night with lid off and it was still full next morning. Now with lid on it will leak empty. Now do I scratch my head or my ****???? lol

 

did they put the overflow valve back in the pump return or did they mess up and put a regular banjo bolt in there?

 

That I don't know. The dealer that did it is in Erie Pa. and I'm here in NC, but I will pass this along to the present tech.
Thanks

 

i wouldnt put anything past the dealers there days. ive seen alot of mistakes. when i first bought my truck the turbo went out and when the dealer replaced it they didnt put the drain tube back on.

 

check the return valve on the IP mine went bad and wouldnt hold any fuel pressure. went to a cummings dearler and got one for about 20 bucks

 

Reason the fuel was still in the bowl as because the filter cap was off... vacuum is created in the tank when the engine is running (pump sucking from tank etc) a normally operating fuel cap will maintain vacuum (small amount, it aids with removing air from fuel shoshing ) IF you have any air leaks on the fuel return side of your truck it will allow the fuel tank to "suck" the fuel from the fuel filter/vp causing hard starts.
you can have leaks from bad injector tube o-rings, or banjo bolt at back of head or the T-fitting near the back of the head, you may or may NOT see actual fuel leaking from these areas, and if you do it will be very slight staining of fuel

to test this theory either park facing down hill or loosen off the fuel cap either one WILL eliminate the fuel tank from sucking fuel out of the filter/vp.
overflow valve replacement is usually NOT the primary cause of hard starts, but it is easy to replace