Hey guys one of my p pump trucks keeps losing prime over night
I cant seem to find the air leak I changed all the hoses tightend all clamps ? it runs perfect once it starts but if it sits over night no start! it only takes about 6-8 pumps on the lift pump and it will fire right up any other places for air to get in? system is clean and dry at all fitting from tank to pump


R

 

Try filling the opening on the preheater where the electric plug goes into it with die-electric grease and then plug back in. This is also a common spot for air to get into the system.

 

If not that, it could be one of the check valves in the lift pump failing.

Does it do it all the time, regardless of how full your tank is? If not, and it is only with a lower tank, it could also be a hole in the pickup tube in the tank.

 

That air leak could even be at the pickup unit in the tank, those elbow things rot out and leak.
Hoses and metal lines are all suspect. You might try pressurizing lines that you suspect and listen for escaping air.

 

double check that ur not having a minor leak from the water separator unit on the fuel filter..the leak is only visible when truck is running and it may just be a couple of tear drops...but it will keep u from starting the next day. I can give u the part # for a solid filter if this is your problem

 

every morning full tank or not ill check this stuff out
thanks guys ill let you know what i find

 

Hey guys i think i found the air leak , i pulled the electrical connection on the fuel strainer and its wet with diesel. is there a way to reseal them, or is a new stainer in the future ?