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    1975 Mercury 850 rebuild powerhead or not?

    Serial 4235590. I think it's a 1975. I have it apart and found what I thought I'd find. The water pump impeller is shot. Top cylinder of inline 4 is not scored, I think. Rings are pretty worn on that cylinder and piston looks a bit ugly. The other 3 cyl. look good and compression was good.... My...
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    Late 70's Mercury 850, Low Compression

    I have a late 70's Mercury 85HP with low compression on the top cylinder. There is also very little water coming out of the pee hole. I was told that the water pump probably failed and the 1st cylinder over heated. Has anyone heard of this? Is this serviceable?<br />The other cylinders run good...
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