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1996 MSHU 9.9 Idling Problem
I have a 1996 MSHU 9.9 with an Idling Problem! HISTORY: The motor sat unused in my garage for a few years. Was told by local Yamaha mechanic that most problems with this motor are fuel related so I have replaced (WITH NEW) the carburetor, fuel pump, electrothermal valve, fuel tank and all hoses. Have sprayed Yamaha combustion chamber cleaner into intake and am running Yamaha ring free cleaner in the gas. Motor starts on 2nd pull but will not idle down... you have to keep wiggling the throttle to keep it running at lower rpm. Runs great at med to full throttle but at fast idle speed the rpms go up and down without moving the throttle. Anybody got any ideas????