Testing Procedure

To check if rough idle is caused by crankcase vent valve connect tachometer to engine, start engine and adjust idle. Clamp off hose from valve to carburetor base. If valve is working properly, engine will drop approximately 50 to 60 RPM.

Fig 1: VENTILATION AIR FLOW

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Fig 2: VENTILATION VALVE & HOSE CONNECTIONS

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Fig 3: AIR FILTER LOCATION

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Fig 4: VENTILATION VALVE

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