Fuel leak and lost prime question???
 

I have a problem with loosing prime overnight. Seems like it started after I removed the fss to put the guts back in, but I'm not sure since it has to sit overnight to occur. All my hoses and fittings appear to be good. I have two leaks. One is where the distributor mates with the housing, and the other one is fuel bubbles at the number 3 injector (not the connection but where the injector mates with the head). Could the leak at the distributor head allow the pump to loose prime? I have to pump the manual lever about 60 times to reprime the fuel system in the morning. I have changed the orings for the distributor head on my TDI with the pump installed (basically the same pump but different number of cylinders), Can they be changed on my truck without pulling the pump again? The leak at the distributor head is a fairly steady drip.

I would get a mightyvac and just put small amount of suction on some lines. If there is a leak you'll see it on the vac, then you can isolated the issue rather quick. 99% of the time if you have rubber hoses then you could get pin holes from corrosion from the fuel tank towards the engine. Other leaks would be noticeable from wet fuel spots from the pump onward.

Already did exactly that bannerd. I did the tank to pump and pump to ip input. I didn't do the lift pump because I didn't know how it would react to vacuum, and don't know about the plumbing in the tank. Anyway, I am pulling the ip now to replace the oring on the distributor head. If anyone has any info or warnings before I start the oring replacement tomorrow I would welcome the info. I only plan to loosen the bolts enough to access the oring (same way I did the seal on the TDI except it is done on the car).

That will work just fine on these pumps. Same as your TDI.[coffee]

Searcher, are you sure the leak is at the distributor head and not leaking from the fss and running down the distributor head?

Positive on that nonrev. Appears to be coming from the lower front area of the distributor head. I switched the oring yesterday and reinstalled the IP today. Pumped it up and no leak, but same as last time, I can't get the darn lines to bleed and now found a new problem. Number 5 injector has a fountain of fuel spraying straight up out of the top of the injector when the line is tight. I've worked on thousands of Cummins engines in the military and never saw that happen.