71 johnson 9.5 high speed adjustment

[red10]

i was wondering if there is a high speed adjustment on the carb. The motor runs great in the spring and fall but in the summer or warmer weather its a dog.

 

[Paul Moir]

Re: 71 johnson 9.5 high speed adjustment

No, there isn't. The mixture is controlled by an oriface located directly behind the obvious looking gasketed screw in the protrusion from the bottom of the carburetor's bowl. The only way to adjust the mixture is by changing the oriface, as long as the float height is set correctly. The float must be adjusted to be parallel with the body of the carb, when it is turned upside-down.<br />If you suspect you're running rich or lean, try reading the spark plugs. Run at WOT for a few minutes with new plugs installed on the water, and kill the engine suddenly. Then remove the spark plugs and examine the insulators.

 

[jim dozier]

Re: 71 johnson 9.5 high speed adjustment

You might go over your cooling system. More likey your engine is running hot and not the carb jets. Thermostat controlled engines with a properly functioning cooling system should not need mixture changes with the warm weather. If you are changing altitude with the season thats another story.

 

[henning_dt85]

Re: 71 johnson 9.5 high speed adjustment

bye colder plugs

 

[red10]

Re: 71 johnson 9.5 high speed adjustment

Henning, what plugs should i be runnin and the gap