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    1986 merc 40hp 4cyl

    Let me clarify, I know im going to need a rebuild. I just can’t seem to find any resources that will tell me where to start? YouTube and Google turned up nothing, I can’t even seem to find a kit for it because all the 40hp 4cylinder kits start at year 1990.
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    1986 merc 40hp 4cyl

    I didn’t know that! I was confused how #4 could top out at 50psi and the other three are a perfect 120. If the motor doesn’t have a removable head then I guess you have to pull the entire power head off to get to the pistons? I’m going to get a camera from Amazon and see what that cylinder wall...
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    1986 merc 40hp 4cyl

    I recently purchased a new-to-me duck boat with a 1986 mercury 40hp tiller. When I went to look at it I discovered it has low compression on the 4th cylinder. It started a little rough, but ran fine on the hose before I found out about the compression issue. I’ve never done a power head rebuild...
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