Question: 1981 Engine miss firing

[johns81]

Wanting input and suggestions. My 81 has a rebuilt jasper engine that was installed about 1 1/2 years ago. Runs like a charm. However, it sat garaged all winter during this past brutal mid west winter. I was able to start it at least once a week, let run for 15 minutes at a time, ran fine. It had about 1/4 of tank of gas. When I as able to take it out on the road, it would appear to be miss firing when I would accelerate moderately. I filled the tank, and in a few minutes, it was running fine again. When the tank got to 1/4 of tank, it exhibited the same symptoms again. Fill the tank, at it was running fine again. At this point I am wondering if the fuel tank has some condensation accumulation from over the winter. I am going to try some gumout that is supposed to remove water for the system. However, I am still a little baffled especially after running another tank of gas through it. I hope that someone has some suggestion, please post reply.

Thanks!!!

 

[Antz81]

If is enough water in the tank to affect it then filling the tank shouldn't change anything as the petrol will just float on top. Could be a problem with your fuel pump or the filter sock in the tank. Although I would have thought that filling the tank wouldn't make a difference if this was the problem. Alternatively a bad connection between the fuel gauge and the sender (or a bad sender) would make the gauge read like there is more fuel in the tank than there actually is.

 

[GerryLP]

If it was stored, and no Stabil or other fuel additive added before storing, you may have bad fuel. Try adding 5 or 7 fresh gallons of fuel. Perhaps?!?!!?

 

[Peer81]

Drive it till the problem reappears. The suck the old fuel out of the tank and put it in some daily disposable car you have on the driveway. After that put 5 gallons new fuel in it you have in the garage, drive to the fuelstation and fill her up. Problem solved at least for the first 3/4 tank

Greetings Peter