I have a 2003 mercury 225 hp oil and fuel injected two stroke. A week or two ago the engine started running hot when running 3/4 throttle. We just bought this boat, and my dad didnt want to take the time to do any maintenance on it before putting it in. There was hardly and water coming out of the tell tale at idle just a drip. Limped it back and pulled it out of the water for the season. Dropped the lower unit, old impeller looked ok, but replaced it anyway with a new housing, impeller and seals. Found fuel filter on engine had collapsed and was clogged, replaced both fuel filters. Also replaced both thermostats and poppet valve. Also did compression test, all cylinders between 105 and 115.
Now the engine seems to run good in the driveway, but still smokes blue after warming up and leaves a sheen in the water. I did notice before we pulled it out that it was leaving a sheen behind the boat, like little specs hitting the top of the water, so it had to be coming out of the exhaust. The plugs are fouled, need to put in new plugs yet. I would think it shouldn't be leaving a sheen or smoking after it has warmed up. This is an electronic oil injection.
Now the engine seems to run good in the driveway, but still smokes blue after warming up and leaves a sheen in the water. I did notice before we pulled it out that it was leaving a sheen behind the boat, like little specs hitting the top of the water, so it had to be coming out of the exhaust. The plugs are fouled, need to put in new plugs yet. I would think it shouldn't be leaving a sheen or smoking after it has warmed up. This is an electronic oil injection.