2004 Johnson 15hp problem

[RFNagle]

Hey All

Have a 15 hp pull start and it ran fine until yesterday. While running full throttle it shut down. After 50 or 60 pulls I got it running for a bit and it cut out again. Never got it running to get back in. Thought maybe bad gas so I switched that out. Pulled the plugs and cleaned them up. Got it running today for 3 or 4 minutes and it cut out with no restart. Seal cover for the thermostat is dripping a bit. Do you think it could be the thermostat itself? Going to pick up new plugs tomorrow but it just doesn't seem like it could be the plug but I have been wrong before.

 

[Daviet]

Re: 2004 Johnson 15hp problem

Have you checked the spark?
Will it run if you squirt some fuel mixture into the carb?
Did the engine overheat?

 

[RFNagle]

Re: 2004 Johnson 15hp problem

Thank you for they reply. I have spark on both plugs and the water pump is spitting water. I haven't squirted any gas into the carb yet. I did remove the thermostat housing and the spring and thermostat are pretty coroded. I did gett it started again and at idle it was fine for two minutes then it reved up a bit and the cut out.

 

[boobie]

Re: 2004 Johnson 15hp problem

How did you check your spark ?

 

[RFNagle]

Re: 2004 Johnson 15hp problem

Took it out and held it with insulated pliers touching the frame and pulled started it.

 

[Daviet]

Re: 2004 Johnson 15hp problem

To get an accurate check for spark you should use an air gap teaster set to 7/16".
The way you described it started and ran for two minutes, reved up and quit, sounds like a fuel problem.

 

[RFNagle]

Re: 2004 Johnson 15hp problem

How long would it take to run bad fuel out? The new 50:1 mix is fresh. It doesn't seem like a carb issue to me what do you think?

 

[Daviet]

Re: 2004 Johnson 15hp problem

As suggested before, if you can keep it running by squirting fuel into thr carb, you have a fuel problem.
Either a pump, carb or restricted fuel lines.

 

[RFNagle]

Re: 2004 Johnson 15hp problem

Spraying gas in the carb made it start a little quicker so I am thinking we could be down to fuel lines or fuel pump.

 

[boobie]

Re: 2004 Johnson 15hp problem

How big of a gap did the spark jump ?? If the spark jumps as posted above you may have carb probs.