# Compression Question



## Brett (Jul 16, 2008)

Less than 2% compression difference between high and low cylinders is good.
The values you read may be affected by the gauge. I have one compression gauge
that reads consistently 10-12 psi lower than my other two. I expect to read 110 psi
on an older motor. Anything above 110 is gravy.  

btw, if I get a sub 100 psi reading, it usually means
I forgot to make sure the intake was wide open, before testing. :-[ ;D


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## Capt Dan Medina (Apr 28, 2008)

I've got a 96 75 HP yam I... compression is the same... runs great...


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