strange engine problems

[ocbaud]

since i've had the rearend in, the truck has been acting weird.

half the time it will haul balls and throw you back really well, but then sometimes, when i get on it, at different rpms(usually around 4000+) the engine sputters and acts like its starving for fuel. I never had this problem with the older gears. I changed the rods and springs in the carb and it seemed to help, but then it started doing it again. I took it out today, it ran great, even at high rpm's, then it started sputtering again, then it quit sputtering about 5-10 minutes later. its an edelbrock 650 avs carb btw.

also...

while the truck was sitting for a month waiting on the rearend, i changed out some of the cooling parts.
i replaced my stuck open 180tstat with a high flow 180tstat. i also changed my fan temp sender to come on at 200 and off at 185.

everyonce in a while, driving around town or down the highway, the temp gauge will shoot up real quick and peg to the top. it kinda scared me at first because i noticed my electric fans werent on. so i manually flipped them on and a few seconds later the gauge went down to normal temp.

now, when it did it again and i wasnt on the highway, i pulled off to the side of the road and popped the hood, again, my fans didnt come on even with the gauge pegged out. there was NO WAY the engine was running as hot as the temp gauge said it was running. The electric fans DO come on at around 200 degrees and i think its just an electrical problem with the gauge somewhere.

it would shoot up to the highest on the gauge with the heater on OR off also.

[piecesparts]

Runs great and then it runs lousey, Hmmmm; could be water in your gasoline. The bowl of the carb could have some water in it. As for the temperature sender; it sounds as if there is a ground problem with the unit, or the wire that attaches to it. The temperature sender is nothing more than a resistance relay that changes with temperature.