I have a 1996 Yamaha 115 that I bought one year ago, from a mechanic who had just rebuilt the motor. I broke it in as he instructed me to, and the motor has run great. Last time I took it out, it ran a little rough, and would kill at idle speed.
When I flushed the motor in my driveway, there was a lot of a black sludge pumping thru the prop with the water. The motor seemed to smoke more than normal. After parking the boat, the sludge dripped down my skeg below the prop, and made a small puddle.
I already checked my gear oil. It is full and clean. The sludge is very black, and appears to include a lot of carbon. I did notice a small amount of gas dripping below the carbs into the motor housing. I found the problem with the gas drip and fixed that, but the motor still produces the sludge when I run it.
Any ideas or advice would be appreciated
When I flushed the motor in my driveway, there was a lot of a black sludge pumping thru the prop with the water. The motor seemed to smoke more than normal. After parking the boat, the sludge dripped down my skeg below the prop, and made a small puddle.
I already checked my gear oil. It is full and clean. The sludge is very black, and appears to include a lot of carbon. I did notice a small amount of gas dripping below the carbs into the motor housing. I found the problem with the gas drip and fixed that, but the motor still produces the sludge when I run it.
Any ideas or advice would be appreciated
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