I've posted a video with the best description and video I could do. Sorry for the terrible camera/flashlight work, trying to coordinate too much and still explain what happened. Here's a quick history: Engine overheats after running at 3500 rpm for a few minutes (will cool down when run at idle). Engine had overheat/low oil/whatever else alarm go off, but temp gauge was failing too, jumping from no reading to 180-190, so I fixed the water temp gauge by replacing the sensor. Took it out again, sure enough, verified with new sensor it was overheating. Engine will run cool if it's below 2000rpm. I suspected the impeller, so I replaced that with a new sea water pump kit. I did find 2 fins broken off the impeller and found them in the oil cooler. Got all pieces out, thought if that didn't work, I'd be replacing manifolds and risers. Took the boat out again. Overheat again when run at 3000-3500rpm for a few minutes. On the way back in, I was idling, then tried to give it some power to see how it would act with the heat up/cool down and I heard a knocking noise. Located it on the port side engine in one of the rear cylinders. Checked the oil, and it was milky. I have checked the oil each time out, and this is the first time I had water in it. I thought blown head gasket, and have taken the engine down to the heads. When I pulled spark plugs they were oily and black and, water came out of the rear 2 cylinders, and both of those cylinders have some rust on them, but the front two and the starboard side seem to be only effected a little by the water in the oil. I couldn't find any area of the head that appeared to be blown out, and I'm trying my best to locate the source of the water. I'm very new to this and am pretty baffled at this point. After looking at the head gaskets, I went back to the port side exhaust manifold. Plugged it and filled with water, but it doesn't appear to be leaking. Not sure what to do or where to go from here. Am I missing something?
Here is a link to a YouTube video where I show as best I can the current state of parts. https://www.youtube.com/watch?v=3exq...ature=youtu.be
Any help is appreciated!
Thanks,
Luc
Here is a link to a YouTube video where I show as best I can the current state of parts. https://www.youtube.com/watch?v=3exq...ature=youtu.be
Any help is appreciated!
Thanks,
Luc
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