I have a 93 F350 IDI turbo that runs fine once it starts but it seems not to be holding fuel in the pump to start. Is there a check valve in there that goes bad and let's fuel drain back down or something? It will crank and crank and not start. Is it time for an electric fuel pump?

 

Welcome, is this happening after it sits overnight or for any start up?

 

Sounds like a comon problem you probably have an air leak in your return lines, they are made of rubber so are the o rings that fit on your injectors so some where in your lines you have an air leak it won't leak fuel just suck air when it sits overnight then it won't start in the morning.

 

I've only had it two weeks and its happened about four times. Today it did it at the mechanics and he said it wasn't holding fuel in the pump. He got it started, I drove it home and about fortune minutes after shut off I tried to start it and the same thing. I'll check those return lines, that sounds the bestcstarying point. How many are there, two? Are they from the pump down the rail to the tanks?

 

Also, when I switch to the back tank the truck runs really rough until I switch it back. Could this have anything to do with leaking return lines? Would be nice if I could fix both problems with one solution.

 

Get someone to turn it over, use a 5/8" inch wrench to crack the two rear injectors when it starts spurting fuel close them and then start the truck. Also there is a check valve in the filter head but iirc it keeps fuel from going back into the fuel return lines, I doubt that is your problem. Some guys go to an electric fuel pump but it isn't like a gas engine air in the system will keep the engine from starting so having an electric fuel pump isn't going to solve that problem. I will try and find a picture of the return lines.

 

https://www.ford-trucks.com/forums/1...p-6-9-idi.html

A lot of good info on return lines in this thread.

https://www.ford-trucks.com/forums/1...ne-repair.html

This one should give you an idea

 

Not sure about this, is the diesel in it really old.

 

I'm not sure about the fuel. I haven't put any in the back tank. The guy I bought it from said he had just put it in it but he may have had the same problem and just been saying that to make me think the back tank was ok.

 

not starting sounds like air intrusion through the return lines or cap o-rings,
rear tank issue sounds like a cracked pickup tube in the tank.

 

Good call TJC I think you are right there. Air intrusion problems all around. The good news is it is a pretty cheep fix.

 

Thanks guys, I'm on it.

 

How do I check for the cracked pickup tube? Will it be obvious just looking at it?

 

Yeah I can't remember how to get the cap off of the rear tank but there is a filter in there and two tubes one is a return line one is the line to the lift pump. It is made of hard plastic and you will see a crack in the lift line.

 

Where's the best place to get the return line kit and the tank fuel pick up tube?