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1977 99 Johnson model 77a Rough Idle

dmschall

New member
"I recently rebuilt an old 9.9

"I recently rebuilt an old 9.9 Johnson 1977 77a model. I had the cylinders bored to .030 etc, replaced pistons, rings, bearings, gaskets,seals, water pump etc..Rebuilt carburetor & new fuel pump & spark plugs as well. The motor starts right up but runs rough especially at idle, but smooths out at higher rpm. I also noticed when I had it running in a barrel of water that water comes out of the exhaust ports. Is this normal ? I am running it with 40:1 oil gas mix instead of the 50:1 recommended mix until engine gets broken in. Could this be causing it to run rough? I tried adjusting the idle mixture screw on the carb. and it smooths it out a little but not much.
I have a very good stream of water exiting the water return hole and the engine runs 120-130 degrees F mostly around 125F.
How is the water getting into the exhaust? I used all new gaskets, cleaned all mating surfaces and torqued all bolts evenly at proper specs. Any help would be appreciated."
 
"i think----u r worrying,about

"i think----u r worrying,about nothing--wtr,does,can,and will mix w/exhaust...it is designed,that way.....more info?...getting in cylinders?"
 
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