I got a 94 Cummins that will run great for about 5 minutes but then acts like it gets air in the lines and wants to die,, where should I start looking for a leak and what psi should fuels be flowing to the pump at, what is the best pressure guage I can get and install to find the leak, I know I already posted about this but I need more knowledge thanks

 

I would look around the injectors first then work your way back to the IP and continue on down the line. If you have access you can put it on a smoke machine or so I have heard.

 

humm i would start at the pickup tube in the fuel tank! if it was the injectors or lines it would normally start off running ruff then smooth out as it builds up psi because you have mechanical injectors. so i would check for small leaks in the back and work up to the front where the injectors are you should have around 20 psi into the injection pump

 

ok how would you recommend checking for leakes

 

The steel lines where they along the frame will sometimes rust and starting leaking. Check them visually, and look for corrosion or dampness. Some of the lines are between the frame and tank though. If you suspect a problem, it may be easier to replace them than look for the leak.

 

will leaking lines cause it to run good for awhile then want to die? or would that be more of a constant thing? just spitballin

 

yes it would because you would suck air