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1983 40c compresion

beltburner

New member
What should the compression be in each cylinder? i'm at 95/90 and wondering if i should be rebuilding the top end over the winter. i'm new to boats but not to mechanics so pls help
 
That is low, perhaps your gauge is off. If not try a can of power-tune and then recheck to see if it helped the rings. You can take off the transfer plate cover, its the cover behind the fuel pump, amd have a look at the cyl and rings. While there you can push on each ring with a screwdriver to see if they are broken or stuck, they should spring back if working correctly. To rebuild the top you have to remove the powerhead and split it at the carb, the pistons are the last thing out, not too hard of a job but not easy.
 
It is just a little sluggish. It runs good but I noticed moisture in the lower
Plug hole so I figured the motor needs to be pulled to do the gaskets anyways.
 
Before you pull it it could be the exhaust plate gaskets on the left side, 2 gaskets and a seperator plate. Plus check the torque of the bottom bolts.
 
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