Carburetor idle screw question
Thread Starter
Racer
Joined: Apr 2008
Posts: 333
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From: Portage Michigan
Carburetor idle screw question
I have an '81 and bought a used '81 carburetor. My friend has been rebuilding it and has it back together, however, we are both unsure of how many turns the idle screws are supposed to set at.
Race Director
Joined: Dec 2004
Posts: 15,030
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Bench setting for an older car should be around 4 turns. This will ensure plenty of idle fuel upon fist start up.
A quick, easy adjustment once running is.....get the engine up to operating temp. Lower the idle speed to as low as it will go(most times, this will be backed out to where the screww is not toucing the throttle. Screw one mixture screw in until the idle gets rough. pull it back until it smooths out and go an additional 1/4 turn. Do the same for the other side. Set your idle speed back to normal.
It is best to use a dwell gauge to make the proper settings, but this will get you by until that can be done.
A quick, easy adjustment once running is.....get the engine up to operating temp. Lower the idle speed to as low as it will go(most times, this will be backed out to where the screww is not toucing the throttle. Screw one mixture screw in until the idle gets rough. pull it back until it smooths out and go an additional 1/4 turn. Do the same for the other side. Set your idle speed back to normal.
It is best to use a dwell gauge to make the proper settings, but this will get you by until that can be done.
