Hi all. First time poster here. I'm having an issue with my 1990 f250 not starting. It's the 7.3 2wd auto. I've only had it a few months and it was running fine and then I noticed it would be tough to start after a couple days of sitting and then one day it fired up for a second and then quit and haven't been able to get it started since. Suspected air intrusion, but because everything looked like it was on there for a real long time, I replaced the starter, glow plugs, batteries IP, return lines, and put in an electric fuel pump to replace the lift pump. Now getting plenty of fuel out of the filter bleed, and good pressure from the filter too. Checked FSS on the IP, and no fuel is coming out of the injectors once I crack them. Funny enough 2 of them were leaking when I got it and now I can't get anything out. Even tried ether as much as i didn't want to ans it sounds like it is a hairs width from starting but it just won't quite catch. And I've had the batteries hooked up to my car to charge during the whole process and they aren't dead or anything. Longest ive cranked it is about 12 seconds at a time. I've read some people say 20-30 seconds, but that seems like a really long time and I don't really want to replace the brand new starter. I really appreciate any help with this, as this is my first diesel.

 

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This sounds like your original problem was a leaking fuel filter assembly (possibly the fuel heater o-ring), and then you complicated the problem by installing a bunch of "new" parts. Im not a fan of the electric lift pump mod. New Motorcraft lift pumps are $75 and last hundreds of thousands of miles. Every hose-clamp and device in the fuel system is another possible air intrusion point. And aftermarket parts are hit-and-miss when it comes to quality and durability.
Have you considered reinstalling the old IP and seeing if it starts.
You can check your fuel return line for blockage.
or perhaps the fuel pressure regulator is jammed (its the black adapter under the fitting that you attached your return line to.) The engine wont run if the fuel return pressure is too hi. As a test, you can remove the return line and route the return fuel out of the IP into a cup and see if you really have flow.

 

Just ran into very near this same problem. My 91 (see sig) ran fine yesterday though I've found it a hard start if it sits for long periods (days) so have begun to suspect the filter heater O-ring since all the injector returns got replaced when discovering a leak at a couple were causing a lope. Went to move the truck today to unload a future project's engine//trans//tcase out of the bed & it caught for a second then nothing. Boat loads of cranking still nothing. Depressed the core on the filter air bleed & got a spit of air then fuel. To be sure there was no trapped air...I had installed an electric pump on the frame between the manual supply//return valves to function in priming...I loosened the filter just enough to let the pump thump away until the filter began to overflow then re-tightened & made sure only fuel came out the bleeder. More cranking. No go.

My GPs are operated manually & are all new. Ran out of light to do it but will check for fuel @ the injectors. The return on my IP is a brass elbow that threads in & has a barbed nipple for the return connection tie-in to #1.

Engine for certain is a little on the tired side & hoping it's not trying to tell me to dump my tax return into it just yet. Just dumped a grand into getting an 87 Turbo IDI Jetta parts car...