How to Adjust Air Fuel Ratio
- 1). Open the hood and remove the air filter. The filter on carbureted vehicles is normally located on the top of the engine. There is a wing nut that holds the cleaning filter to the carburetor. Turn the wing nut counterclockwise and pull the filter off. Do not remove any of the hoses connected to the filter; just set the assembly off to the side.
- 2). Locate the two screws on the lower front side of the carburetor.
- 3). Turn the screws clockwise until they are tight and will not turn anymore.
- 4). Try to start your vehicle. You may have difficulty starting the vehicle. This is OK. Turn each adjustment screw on the carburetor counterclockwise two complete turns and try to start the vehicle again.
- 5). Repeat step 4 until your vehicle starts normally. Keep adjusting both screws on the carburetor until your idle smooths out and holds steady somewhere between 500 and 800 RPMs on your vehicle's tachometer.
- 6). Put the air filter back and tighten the wing nut when you are finished adjusting the carburetor.
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