I just bought this 90HP and found that it hiccups at idle speed. It also will start up fine but after 15-20 seconds it hiccups and shuts off. Restarts ok and when it is above idle speed it runs great. Only does this at low speeds around 800-1000 RPMs. Runs fine at top end.
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I cleaned the carbs, which looked clean to me other than some corrosion in the middle carb bowl and around the fuel enrichment pump assembly. I*disassembled the assembly, cleaned it and tested the electrothermal*valve resistance and valve height per manual. All looked well.
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I*adjusted the low speed jets and*put in new plugs. After putting it all together again I expected my hiccups to go away. That isn't the case. I still have the original problem. However I gained a*lot of experience with the Yamaha engines.
*
Does anyone one have any suggestions on what to do next?*
*
Rich*
*
I cleaned the carbs, which looked clean to me other than some corrosion in the middle carb bowl and around the fuel enrichment pump assembly. I*disassembled the assembly, cleaned it and tested the electrothermal*valve resistance and valve height per manual. All looked well.
*
I*adjusted the low speed jets and*put in new plugs. After putting it all together again I expected my hiccups to go away. That isn't the case. I still have the original problem. However I gained a*lot of experience with the Yamaha engines.
*
Does anyone one have any suggestions on what to do next?*
*
Rich*