Gmc 366 Idles High

[subs1000w]

i just got a 87 gmc 6000 65pas school bus with the carb 366 gas engine and 5spd trans and it runs great i guess besides the lack of no power but i think thats normal but it seems to have 2 problems one the coolant temp gauge dont work but hopefuly thats just a wiring thing the second and more important problem is it seems to idle really high sometimes and somtime the idle will go back down to "normal" it doesnt have a tach "yet" so i really dont know what its idling at but i would guess in the 2000 range any thoughts on this would be great also the engine seems to have a governor on it and im just curious as to what those are ussually set at im guessing in the 3000-3500 range thanks

[doverarjim]

Not quite the same motor but my 86 GMC with 350 always since new, when started even when it was already warm would run up about 2500 RPM until it was warm which would only take about 3 or 4 minutes. My guess was that it used regular leaded (yes I said LEADED GAS) had something to do with it. I never asked the dealer because the techs he had were just parts changers and did not know much about the real reasons things worked like they did. As far as I know there is nothing you can do about it, it just helps get the thing to temp to put out less bad stuff. Hope this helps!