My '94 f350 doesn't get used as much as it used to but I have been keeping it running and taking care of some odds and ends on it lately. The glow plug module wasn't working recently and after some searches here, came to the conclusion that it was the ground. It was, I cleaned that up and it started much better. I had a leak from one of the injector cap o- ring deals, replaced that and all was well. Also changed the fuel filter about a month ago. I have put about 80 miles on it over the last few weeks , driving it occasionally. Today, it started right up, I drove about 30 miles to work and parked iit for about an hour. When I tried to restart it, it fired up, sputtered and stalled. Waited about 30 seconds or so, it cranked longer then started. I gave it some throttle, it leveled off and ran fine. Stopped again a while later with the same scenario.
When I got home, I checked for leaky fuel lines? or anything obvious. I did a search and have read some about air intrusion but not sure where to look.
Any help would be appreciated.
Bill

 

What's your battery voltage? before cranking, and while idling?

 

Didn't notice the voltage. The batteries are less than a year old. I am planning on taking it to work in the am (if it starts ok) and I will check the v's. I am no mechanic, but have been through quite a lot with this old truck. Sure seems fuel related but I have been wrong many times in the past.

 

Could still be fuel related, but it could be your batteries, alternator, or starter. You need lots of volts to start these old beasts. If you are anything less than 12.2V before cranking, it'll crank, but not start. If your batteries are new, then look at your starter, or maybe your alternator is somewhat working. Maybe your batteries aren't getting a good charge from your alternator. How old is it?

ALso, you should check to see if you have a key-off drain on your batteries.

I would think if you had air intrusion, you'd have some surging while driving or loss in power. Maybe you have a return line that is cracked, and you are losing your diesel prime everytime you start. But just by the way you described your situation, and by the way your truck sits all the time, I'm thinking it's something electrical.

 

typical air intrusion the engine will start then die 40-50 seconds later, this is because the air leaking into the fuel system can draw down the filter, the vertical fuel line down to the ip holds only enough fuel to sustain the engine for 40seconds or so. common leak location's are injector orings and fuel heater electrical connection on top of the filter head, and fuel pump, so because it starts, it's proly not gp's, not starter, has some one omitted the return line on top of the fuel filter head?.

 

air intrusion. when you replaced the ONE injector cap o ring, you disturbed the ones on each side and they are now sucking air.

it is recommended to always do all return line caps at once. doing only one will result in the problems you are now having.

 

Thanks for all the advice.
The problem turned out to be the fuel pump. I was really focused on it being a fuel issue since the batteries and the starter are both less than a year old but what was puzzling to me was that I didn't see any seepage or wet around any of the return lines, etc. I was prepared to replace them all anyway. I did a search here and google just before I went to the parts store and read several threads about air intrusion and the lift pump being the culprit. 25.00 was easy money to spend if this took care of the problem. I replaced this first. Of course, the steel line from the pump to the filter housing broke off (badly corroded) in my hand so I had to make a new one.
Once the new pump was installed and I got the air out of the system, I am happy to say, the truck starts better than it has in a while!
Thanks again for all the help.
Bill