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'93 IDI fuel problem

3K views 8 replies 6 participants last post by  Snotzalot 
#1 ·
'93 F350 crewcab 7.3 IDI, 212k miles, auto

One day last week I filled up the front tank at a mom-n-pop store with diesel. The truck ran fine for an hour and a half going to work. That evening it would not start. The batteries are new and the crank speed is fast. After switching the tank selector switch back and forth and pumping the accelerator pedal, it finally started but ran and idled very rough. I drove to the nearest large gas station and filled the back tank with diesel, which was about empty. After running on the back tank for 5 minutes or so the engine smoothed out and ran fine for 2 more days. So, I chalked that up to bad fuel in the front tank and was only going to use the back tank. This morning after the usual hour and a half trip back to work on the same fuel in the back tank, as soon as I rolled into the parking space the engine died and would not start again and I'm currently stuck at work. The back tank is now down to just over a quarter tank.
My plan is to get 10 gallons fresh diesel in cans and pour in the back tank and check the fuel filter water drain, and if that doesnt work, pull the fuel filter and replace. No lights came on on the dash.

Is there anything else I should check?

I looked through the forums about a guy I remember found fuel lines that had deteriorated and were leaking air or something but I couldnt find it.

I read somewhere that it doesn't help cracking the injectors' fuel line because fuel may be there but the pressure may not be enough.

The injector pump is 1 year old and the fuel filter is 6 months old.
The truck ran fine until the fuel level got low in the back tank.

On both back tanks, the filter sock screen thing has come off the bottom of the pickup pipe and it technically runs out of gas at a quarter tank but the current level is just under a half tank now.

Please help
 
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#2 ·
Might want to try....

Draining fuel into clear container to see if it has anything nasty floating around in it. I had this problem once and it turned out to be a bad batch of fuel with some unidentifiable crap in it. Keep us posted.
 
#4 ·
AHHHH Mom and Pop stores.......... If your tank pickup(s) is broken fix it ASAP.... No telling what is floating on the bottom and finding it's way up into the fuel getting passed to the IP.

If you want try doing a fuel burn test/smell on the fuel you got from Mom....... it could have gasoline in it by mistake. This would not be a first time a tanker driver pumped the wrong stuff in the wrong tank.......

Get some diesel fuel additive and fill the filter first when you install the new filter...... It will take some extra cranking on the starter due to air intrusion since you removed the filter.........
 
#8 ·
AHHHH Mom and Pop stores..........

If you want try doing a fuel burn test/smell on the fuel you got from Mom....... it could have gasoline in it by mistake. This would not be a first time a tanker driver pumped the wrong stuff in the wrong tank.......

You're right the fuel was contaminated. I siphoned the tank and the diesel was the color of miller light or like new motor oil, not the clear greenish-yellow diesel color at all. Once the white 5-gallon plastic paint bucket I was siphoning into had about 4 gallons in it I could no longer see 'through' the fuel to the bottom of the bucket. Filled up with 15 gallons of fresh diesel from the Exxon station and it's still going strong.
Thanks again to everyone.
 
#5 ·
This is what I do once a month, or when I have problems. Drain the water from the filter. At every fill up I use 2-4 ounces of DieselKleen 911. After draining the fuel filter of water, you can crank the engine, but I would bleed the system since it hasn't started. The is a little valve on the filter assembly that has a tire valve type cap on it. you can push it in just like a tire valve. You will need a buddy for this, unless you have a tire valve core remover. Push the valve in, or remove it. Crank the engine until you see nothing but a steady flow of fuel from it. Replace the valve core, and see if she starts!
 
#6 ·
The is a little valve on the filter assembly that has a tire valve type cap on it
That is the Schrader valve.....anytime the core is "removed" it allows air into the system......until the filter is refilled and the valve core is replaced.

So what air comes out may be what you induced by removing the valve core..

Read up on "clear hose test" and filter air intrusion points on......

Ford diesel 6.9 7.3 IDI
 
#7 ·
Thanks for all the replies guys.
When I got off work, after the truck sat for 3 more hours, it started right up and ran smooth, without doing anything to it, still on the back tank.
I went and filled the tank all the way up again and it's still going strong.
Seems to do OK as long as the tank is almost full.

I'll follow your tips and post back with the results.

Thanks so much again.
 
#9 ·
It sounds like bad fuel in the front tank and a bad pick up in the rear tank!

Glad you found the trouble!
 
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