If your Cushman Truckster has the problem of backfiring or the engine misses when under a load, the carburetor could need cleaning or some other condition exists in the engine.
The engine should operate fine when the carburetor is adjusted within the range of the specifiction section. Carburetor high speed adjustment…2 1/4 turns open; Carburetor idle speed adjustment…1 to 2 turns open (approximate)
A leaking carburetor indicates a defective float, defective inlet needle and seat or incorrect float setting. If the float setting is incorrect you can put light finger pressure to the float arm to obtain the correct setting.
There are three different carburetors used on the Cushman Trucksters. The Carter, Keihin, and Zenith are three different carburetors used depending on the year or model of your Truckster. You will find diagrams of each below.
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