1979 55hp won't idle

[mcwashington]

Have recently pulled the carbs and cleaned them thoroughly. However, the motor still will not idle below 1/3 throttle. BTW, have also replaced the fuel pump and currently using fresh fuel.

Any advice?

[Elton Smith]

Theres a screw on top of the carb that has an idle orfice.Take some carb spray with straw and blow that out. see if that helps.Click boats.net in the left hand colume of this page,look your model up and you will see it.

[Tembouk2]

bad idle

I had a 1995 115 johnson doing that. This engine had truely been used. i made do for 3 years and couldn't take it no more so i did a refurb and NO more trouble. compression is a large part of a 2 stroke running smoother.

[djockey21]

Rough Idle

I have a 70HP 1994 motor. I had a hard time idling as well. I am here at the beach and took it to a friend of mine. They looked at it and said that there was no thermostat in the engine. I bought this boat used and motor. Didn't think about looking to see if there was a thermostat. Well I had him put one in and now my boat idles fine.

The reason why the boat will not idle without a thermostat is because the motor doesn't know how hot the engine is to shutdown the motor to idle. The temp to idle is around 130-135 so once the engine gets that warm in neutral it will shutdown and Idle.

I had to put in a new thermostat and a new temp sensor switch.