May be getting close to figuring out my problematic 150 HP Johnson 2 Stroke

[newenglandguy]

Has always been temperamental starting. So far, last year I built the carbs. Definitely helped, as I was having a problem bogging down and it has always been a bear to get started and warmed up. So it's been running fine and all of a sudden can't get it over 2000 RPMs without holding back, sl tallying, etc. so sitting there in the water, get it started and as long as you choke it just a wee bit, she idles. Shut the choke off and she spits and sputter and when working throttle linkage she won't go much above 1500 RPM or so. So guy with me says crack open the choke a wee bit and sure enough she idles pretty good. Hit the throttle and I easily get it above 3000 RPM without missing a beat. Rev up engine, again with choke slightly on, and she runs like a champ. Shut choke off and right back to spitting and sputtering and again, can't get it to go above idle without bogging, or spitting or sputtering.

What does that sound like. I think it's definitely fuel related but what is it?

One thing I see, and I don't know what is is - but just before the 3/8" fuel line goes in to the fuel pump on left side of motor there is a tee with probably a 5/16 or slightly smaller house. It goes to some white plastic "valve looking thing" and the valve has some electromechanical switch with two wires going to it. What is this little bugger and is it part of my problem?

Thanks

 

[misery]

Re: May be getting close to figuring out my problematic 150 HP Johnson 2 Stroke

What year is your motor? I had an 86 johnson 150 hp that i fought with for a month to get it to run right. The symptoms you describe point to a fuel issue. Have the carbs been gone through yet? The part you are describing sounds like the fuel restriction warning sensor and it won't affect the running of the motor unless it has an air leak of some sort. Have your carbs disassembled and cleaned and make sure all of your fuel lines and connections are in good shape and tight.

 

[newenglandguy]

Re: May be getting close to figuring out my problematic 150 HP Johnson 2 Stroke

It's a: MANUFACTURER: Johnson YEAR: 1989 HORSEPOWER: 150 MODEL / SERIAL: J150STLCEM

 

[Watermann]

Re: May be getting close to figuring out my problematic 150 HP Johnson 2 Stroke

Could be starving for gas if using the primer to add fuel makes it increase in RPMs. Have you looked into replacing the fuel pump and filter?

 

[newenglandguy]

Re: May be getting close to figuring out my problematic 150 HP Johnson 2 Stroke

Thought I mentioned it but did install a new filter.