I went to have a fuel pressure guage installed today. Just as in my nightmares, the mechanic called back and said there was no fuel pressure and the fuel pump was dead.

My question is this, WHY IS THE TRUCK STILL GOING AND HOW BAD HAVE I TRASHED MY INJECTION PUMP.

 

i ran the first 30,000 miles with a bad pump, the second lasted about 40,000... i installed a pusher pump when the pump started to lose pressure. have not had any problems since(165,000)

 

The injection pump also has a small fuel pump that can provide enough fuel to feed the Cummins on it's own.
The lift pump's job is to feed the little pump making its job easier, as well as providing an excess of fuel to cool the injection pump.
The (now hot) excess fuel is returned to the tank to be recirculated.