CAn any one tell me why my 98 12 valve would lose fuel prime. If the truck sit for 48 plus hours. It start right up, runs for 30 sec. and quite. I then press the pedal full down and crank until ti picks up fuel and stays running. The problem is a real pain in the AZZ. and ideas would be a great help. awinn@state.pa.us Thanks Rich Winn

 

check ur fuel lines... do a search for fuel lines the older trucks with ruber lines have a tendancey to deteriorate. there are some by the tank and in the engine compartment.

 

The complete fuel system has to be "AIRTITE". From the tank to the lift pump and injection pump, and the return line also. Any air leakage will allow fuel to drain back. Troubleshooting takes a systematic approach. Worst problem is the line from the tank, (including the pickup assembly inside the tank), to the lift pump. It has only suction on it and is hard to find leaks. From the lift pump on, the fuel is pressurized when the engine is running. Therefore, it is relatively easy to find a leak under pressure. Sometimes the return line will decay and leak (rubber). To get that to leak, you sometimes have to restrict the return line at the tank to get pressure to develop in the return line to see the leakages.

 

I'd go for the rubber fuel lines in the engine compartment. Mine has done the exact same as you describe and i found the return line was cracked. I replaced both of them down to the junction on the frame . good luck they are lot's of fun to do but not that hard just a pita ???