honda gx390 compression in psi?

ruicunha

Member
Tried searching on internet and i cant find the answear for gx390 psi stock compression value. anyone knows? Thanks.
 
8.2 : 1 Is compression ratio
Don't quote me on this but I remember seeing around 85-100 psi is good compression for them on the internet. If it is a worn motor I think I have heard around 70psi
 
Compression will depend on cranking speed, and valve lash, if the compression release is still installed and functional.

A leak down test is more representative of engine condition.
 
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