Sounds like the float in the carb is stuck open to me. The wide open to keep it running and the belching black exhaust are the clues.

If its a Rochester, the float may be rubbing on the casing causing it to stick. The needle valve on the float may also be stuck open.

Last edited by Phak1; 06/16/2021 1:32 AM.

Phil
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1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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