Expert: Skip Bollinger - 11/30/2006

Question
I own a 1990 Ford F250 7.3L n/a automatic diesel 4x4.  We have just recently experienced very cold weather (+7,-20f).  I leave this truck plugged in when at work and all night, but when leaving work I started the truck and it idled very radical and soon stalled.  Upon restarting it the truck was very hard to start and keep running.  I put some anti gel (diesel 911) and was able to start it and hold it at 1200 rmp.  The truck would not stay running and would stall out no matter what I did.  Now this has a full tank of Diesel and the engine was running at temperature, I also just changed the fuel filter and oil.  A couple mechanics suggested that the lift pump (or transfer pump) could be bad.  I would like to get your opinion on to what else I should check on this Truck.  The vehicle has only 175,000 miles on it and was very well taken care of by the previous owner.  I purchased it 10,000 miles ago.  Thank you for your time.

Justin

Answer
Justin,
  Let me begin by saying I'm NOT qualified to answer this question. I'm a Parts Professional but am willing to give you my best thoughts on your problem. If you feel you will need to criticize me with my answer, I'm sorry. I'm just trying to help you.
  Once diesel fuel has gelled, you can't fix it unless you get the vehicle in a warm area to let it thaw. IF you have not done this, I think the stuff is just too thick to flow. It is like water in gasoline. Once it freezes, you can ad all the Heet you want but it won't thaw the water. I think it just needs to be thawed out.
  As far as the transfer pump goes, if it can't pick up frozen fuel... well you get the idea.
  My first thought would be to get the truck into a warm garage and let it sit for a few hours. Then try to start it. If it starts and runs well, THEN add the anti-gel. If it DOESN'T start or runs like you described, then run a fuel pressure check to see if one of the fuel pumps may be going bad.
  Justin, again, I'm no Tech. I'm a Parts Professional. I just hope these thoughts help you a bit. Good luck..
  Skip
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