Suleiman Saadeh
Full Access Member
1994 F250 7.3 IDI
Truck will start sometimes but other times not at all. Drives fine once it cranks. No irregularities. I was getting air in the lines so after some digging i found a leak in mechanical fuel pump and replaced it along with the rubber grommet around the metal pipe going up from the pump to the fuel filter. I have a clear vinyl line replacing the return line running from my front most driver side injector to the top fuel injection pump to see if air was still coming through after the new fuel pump was installed. It cranked up after I installed the pump and I watched line till no more air came through except the extremely tiny bubbles that I assume are normal. (Correct me if I'm wrong). It started fine after the lines filled up with diesel. Drove it around, came back home. Turned it off. Came back 30 minutes later and it wouldn't start. There was a big bubble in the return line that floated up from the injector and while it was being turned over the fuel in the return line wasn't moving like there was no pressure from the injection pump but there was pressure an hour before and that is what keeps happening. But the Schrader valve would pump fuel.
I'm not sure if the injection pump is going bad or just needs maintenance. I cant say for certain without purposely trying it out but it seems like when the engine is cooled and not been ran itll crank up but once its warmed up and the engine is hot the fuel injection pump does not push fuel.
I'd greatly appreciate some advice or feedback. I've looked for a thread as close to mine as possible before posting but havent found one that quite fits mine.
Truck will start sometimes but other times not at all. Drives fine once it cranks. No irregularities. I was getting air in the lines so after some digging i found a leak in mechanical fuel pump and replaced it along with the rubber grommet around the metal pipe going up from the pump to the fuel filter. I have a clear vinyl line replacing the return line running from my front most driver side injector to the top fuel injection pump to see if air was still coming through after the new fuel pump was installed. It cranked up after I installed the pump and I watched line till no more air came through except the extremely tiny bubbles that I assume are normal. (Correct me if I'm wrong). It started fine after the lines filled up with diesel. Drove it around, came back home. Turned it off. Came back 30 minutes later and it wouldn't start. There was a big bubble in the return line that floated up from the injector and while it was being turned over the fuel in the return line wasn't moving like there was no pressure from the injection pump but there was pressure an hour before and that is what keeps happening. But the Schrader valve would pump fuel.
I'm not sure if the injection pump is going bad or just needs maintenance. I cant say for certain without purposely trying it out but it seems like when the engine is cooled and not been ran itll crank up but once its warmed up and the engine is hot the fuel injection pump does not push fuel.
I'd greatly appreciate some advice or feedback. I've looked for a thread as close to mine as possible before posting but havent found one that quite fits mine.
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