1999 Johnson 250hp V6 Compression #'s

CaptainHook

Petty Officer 1st Class
Joined
Mar 18, 2010
Messages
310
I am going with my brother to look a his potential next boat this afternoon. The boat is powered by a 1999 Johnson 250hp V6 outboard.

I am going to give it a quick inspection and compression test. I am wonderiong what I should be looking for as far as conssidering this motor to be healthy.

I know that all cylinders should be relative to each other but should it be in the 120-150 psi range? I only ask as I looked at a 225hp last year that was a good runner at about 95 psi on each cylinder. I passed on that one because I thought those #'s were low.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: 1999 Johnson 250hp V6 Compression #'s

No. The big V6s are low compression engines and typically compress in the 80-90psi range.
 

CaptainHook

Petty Officer 1st Class
Joined
Mar 18, 2010
Messages
310
Re: 1999 Johnson 250hp V6 Compression #'s

Wow, I did not realize that. What is considered tired? Below 80?
 
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