95 Johnson 200 won't idle

[jeremyeasen]

My 1995 Oceanrunner 200 would occassionally stall out while idling, but it's getting worse. I changed the plugs and its worse (same plugs QL78YC). The old plugs were not fouled. A mechanic last year installed 133 degree thermostats and this seems too cool. At cruise, I run 160 degrees per the OEM water jacket gauge, and at 800 rpms at idle its 125-130 degrees. This seems too cool. It idles fine until I get to 130 degrees, then starts stalling. Should I be using the 133 or the 143 degrees stats? Thank you.

 

[jeremyeasen]

Re: 95 Johnson 200 won't idle

any thoughts?

 

[tashasdaddy]

Re: 95 Johnson 200 won't idle

143 stat, it starts to open, full open at 160. you may have low speed jets clogging. have you ever decarbed it? you you run seafoam or other stabilzer in your fuel?

 

[jeremyeasen]

Re: 95 Johnson 200 won't idle

I could probably stand to de-carb, i had them rebuilt about two years ago, but I do a lot of trolling and pre-mix. I'm going to do the Seafoam clean out this weekend. I've found mixed information as to which is the proper thermostat for this engine. Is the proper thermostat a 133 or 143 degree? thank you

 

[tashasdaddy]

Re: 95 Johnson 200 won't idle

the correct one is part # 437090, and doesn't say temp. the sierra aftermarket replacement is 133* decarbing has little to do with the carborators. it gets the carbon out of the guts of the engine, rings etc. i don't know what plugs you are using, but i do know that setting the gap ..005 more than recommended helps when doing a lot of trolling and slow running. on the small engines, and additional .010 is added.