Hi all, Had a question about my truck. I put a 283 into my 65 GMC 3/4 ton. I had it running and have been driving it for about a month now. all of a sudden last Wednesday it decided not to idle on its' own. It did seems that it needed additional timing with a light. I had to advance the timing to get it to run. It sat on an engine stand for about 30 years in my fathers garage before that. I can drive it and it starts and runs fine just so I keep the idle up with the gas pedal. Once you let off it dies immediately. I had the alternator tested. The guy ran it three times. It is OK. I changed the fuel filter. The mechanical fuel pump is new and I even run a back up Electric one just in case I need it. I set the idle adjusting screw down as far as it will go and still nothing. I had previously backed it off because it idled far to fast for my liking. Could it nee to be retarded a bit now that it has been running and the timing is out now that everything has been lubricated and broken back in? Could the carb need additional adjustment? Before it went in the carb was rebuilt, but I cannot guarantee the setting on the fuel and air mix. Any help to point me in the right direction would be great. It has everything new form the point/condenser up to the spark plugs. Thanks all.
distributor hold down loose..? has the distributor turned...? my model a with hv oil pump , will turn the dist. and it will not idle at all...move it back to the mark I made on base of dist and intake and we're good as gold
Over the net, is not easy; If all of a sudden, it could be something plugging the idle circuit in the carb. Got a compressor and blowgun? Take out the two idle mixture screws, spray in the holes with carb cleaner, then use air blast. Also could be a sudden moderate vac leak like a medium size hose fell off? Also suck on the vac advance unit hose to see if it can move the point plate with dist cap off to see. Or does it just do nothing and seem like it has a leak? New points when? check to see if the gap is still OK, as the rub block may have worn down.
all good ideas above. did it backfire through the carb? if it has, it could have blown off a vacuum hose or blew out a gasket.
I agree sounds like an air leak on the carb or fuel starvation issue. Have you pulled the plugs to see if it's running lean or rich? That might give you some indication of where to start looking. -Ben -- http://www.drillist.com - Hot Rod classifieds done right.
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