fuel additive problem?
My 3 cyl diesel has only failed twice in the 15 years it has been used. Both were the same situation. About 20 mins of run time after filling the tank the engine stops. No smoke, no alarms, no low oil pressure, no evidence of overheating, just quits. The racor bowl is clear, no water or gunk. I pumped fuel out of the bottom of the tank, it looks perfect. The first time (last summer), after towing the boat (30 feet, 6000 pounds) back to the dock with me rowing the dingy, a great work out by the way, I got it started by just cranking for awhile. I purged the fuel system and replaced both filters just to be safe. After that it ran perfect for a year ON THE SAME FUEL until today when I put 8 gals in the tank. Then it did the same again. It would re-start, run a few secs, then died. The third crank it ran fine all the way home.
I am wondering if the culprit is the biocide I put in the tank just after filling both times. It is pretty thick stuff. My theory is that it settles to the bottom of the tank and after the fuel in the line and 2 filters is burned. It then enters the engine without enough dilution and the engine will not run until it is pumped through by cranking and stumbling for a bit. Has anybody had a similar problem? Any other ideas?