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1983 Evinrude 140 Hp compresion question
- Thread starter sacalait
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There were so many different configurations of pistons, piston ring heights, port heights, and cylinder head changes going on in the older crossflow V4 family that it would be pure luck to know what it should be on your engine. This is especially true since yours has been rebuilt. The rule of thumb in the OMC manuals is that the compression should be within 10% of each other.
lckstckn2smknbrls
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Anything over 100psi and within 10% of each other would be good.
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Not necessarily! There were several model years that had compression numbers of less than 100psi. Use the 10% and go with it.
Well the compression on all cylinders was withing 10 psi of each other acctually only one was off by 5. Which I thought for the age of the motor was good. Anyway bought the motor and it runs great no problems. Thanks for the input.
