1999 johnson 4-stroke, 9.9 hp

have a chance to pick up this motor for 300 smackers. the catch,? gas in the oil. my question for repairs, will it matter if this motor was run for 50 hours or 5 minutes. trying to get a feel for what kind of damage i could expect.

thanks for any heads up

The gasoline in the engine is more than likely caused by blow from worn out piston rings or rings that where not broke in properly. Most start with replacing the thermostat with a hotter one to increase the temp. New thermostat and oil change cheap and easy. With the 9.9 the problem lies in that most of the time they are a kicker motor and don’t get up to proper operating temperature enough as most usually run them slow for trolling. Hence the gasoline seepage. Running a hotter thermostat will let you run slow speeds but heat up the rings so they seat “seal” better. You may also want to prop to a smaller pitch, if engine is under constant load from over propped it will seep gas. For $300 I would buy and change out the thermostat and oil and see what happens.

got her for two hundy, oil resivore was full of gas though, not much oil. will do the thermo and run her hard see if it holds up. the boat it was on looked tuff as well, should at least get parts money from her!

thanks for the “easy” road, I was not even thinking along those lines. even if it turns out to be a bomb, i figured it was worth a shot.
fieds

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got her for two hundy, oil resivore was full of gas though, not much oil. will do the thermo and run her hard see if it holds up. the boat it was on looked tuff as well, should at least get parts money from her!

thanks for the “easy” road, I was not even thinking along those lines. even if it turns out to be a bomb, i figured it was worth a shot.
fieds

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Look at it this way… a new prop for a kicker costs a hundred bucks. You got the whole thing for two. I think you’re going to come out fine on this one.

i think you’ve got a real good shot at it coming out fine. agree with the thermostat change. if you are still getting gas in the oil, one we used to do in my ‘stockin’ days was to add some silver polish to the oil for about ten minutes of run to see if that will help the rings set up better.

if that doesn’t work (50% chance) give me a buzz and we’ll see what the country boys will do on those two cylinders. i’m guessing $300 to $400. You’ll still be money ahead…