Howdy y'all,
I've got a '90 F250 with the 7.3L in it, and I'm having some sort of fuel delivery issue, I believe. Here is what I have done recently: new fuel return line kit (yes, new washers and o-rings on injectors), replaced other old fuel lines in engine compartment, all new glow plugs, new glow plug relay (cuz the indicator light was only staying on for approx two secs), proper aftermarket fuel filter, and tightened up any loose fuel line connections ( I did find a leaker).
At this point, the engine compartment is dry, no fuel leaks underneath, but I still have to pump on the "gas" pedal to get the truck to start (usually takes 3 times to start).
So......still more air intrusion? Bad lift pump? I would really like to get this truck to start on the first crank, so any help/suggestions are appreciated. If this exact scenario has already been covered, please link me to the thread. Thanks in advance!!

 

Welcome to the site..

Condition was present 'prior to all the line work? You didn't mention the injection pump. Age is ? Lower fuel sulfur, blends, along with age failed quite a few early pumps even with only moderate mileage. Once it fires, how does it run? Rough/rattle, or heavy or abnormal smoke with misfire?

You could install clear return line/s and look for air, but if there's abnormal smoke it could be a pump. More so if it's OE or an early replacement.

Is it hard to start through out the day? just cold, hot soak? Lift pump pressure/volume check would be easy enough, air intrusion unless from the tank given the hose/ring etc. sealing should eliminate those possibilities..

 

I didn't mention the injection pump in hopes that it wouldn't be that part😬. I don't know the age of the pump; it could easily be the original.

Once started, the truck runs great! No rough rattle, misfire, smoke, etc. Startup is difficult when cold, or if it's been sitting for more than approx 20 min (after getting hot).

 

Hey guys! watch the following link. Hope it will help you.
https://www.youtube.com/watch?v=CtXp6RA9cYQ