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1968 9.5hp uneven compression?

S

sailor88

Member
Hey! All: I have a 1968 9.5hp Evinrude model 9822. When I first got it, the upper cylinder compression was 70, lower was 63. I since then replaced the head gasket, thoroughly cleaned up the head cover, after that, the compression raised to 80 up and 72 down.

Here are my questions:
1 Should I be concerned about the uneven compression?
2 If yes, is there any product out there that might restore the compression? I think those white can with blue cap engine restorer are not formulated for 2 cycle engines?
 
Probably has stuck rings. You can try the engine cleaner products if you want to. Personally, I have little faith in them
 
I would run it when you can and recheck. 7 or 8 pounds difference is not the worst for a decent running 9.5. Try both cold test and warm motor test. It might come up when warm.
 
Compression gauges can often be inaccurate for a number of reasons. Try it on your lawnmower to see what it reads. When was it last running?
 
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