Yesterday while towing a fifth wheel, my 96 12v quit accelerating and coasted to a stop, throttle input had no effect on RPMs. It hasn't started since. it turns over easy, but no combustion is occurs. I cracked the fuel line coming into the injection pump and fuel came out. Unfortunately, there is no fuel on the output side of the injection lines. any ideas? besides buying a new p7100 (which i can't afford right now)

 

Check the solenoid on the side of injection pump. Does it lift up when you have someone turn key to crank position? If not read diag procedure attached. Also check fusible link wire locaterd at drivers side battery for corrosion or burnt fusible link wire. Replace if burnt out with same gauge fusible link wire.

 

The usual cause is a cracked fuel line in the tank on the pick-up tube, but if it passes a fuel flow test after the transfer pump I would check the following:

Check your shut off solenoid and make sure it is properly lifting the linkage on the side of the injection pump. It should pop right up when you turn on the key.

The other thing to check is the overflow valve that is located on the inside of the pump and regulates the head pressure and returns excess fuel to the tank through the return line. If the pressure relief spring breaks it will flow the fuel back to the tank and not properly charge the delivery valves.

If you have not done a flow test, then do that first. As you just may have cracked or perforated fuel lines that are allowing air infiltration, or it may be the tank pick-up. Do not forget to check the flex lines on top of the tank if it will not pass a flow test.

These injection pumps seldom fail, and when they do it is almost always slowly after close to a million miles. They will get hard to start when hot, lose power in hot weather, etc. They hardly ever just conk out unless the fuel profile cam has been removed and the fueling follower is allowed to hammer, then they just crap out, but there is even a rule for that. It has to be in the middle of a snowstorm and 60 miles from civilization!

 

It will only pop up when you turn the key to crank. Run key position only holds the solenoid up.