How to Adjust Air & Fuel Mixture on a Vehicle's Carburetor

Video Transcript

"To adjust the idle circuit fuel mixture, what you do is take a screwdriver and turn the screw in until it slows down the engine. And then you pull it out a half a turn until it speeds it back up. Do it on both sides of the carburetor. And some carburetors will have four. Some will have two. And depending on the model type, they might not have a screw, but they will have something similar to it. But all you've got to do is turn it in until it slows down. Then pull it out half a turn, and you should be set for your idle mixture. All right, to locate the screw, it'll usually be right on the metering block, if it was a Holley carburetor. And if it's an Edelbrock or any aluminum four barrel, there will be two screws in the front of the four barrel. You just turn them until it slows down, same process as it would be on the Holley. Just the Holley would be on the metering blocks on the side, and the Edelbrock would be in front."