did compression test, what d'ya think?

Dan Beisel

Petty Officer 3rd Class
Joined
Sep 3, 2003
Messages
76
OK I finally got my 1970 Johnson 115hp all back together after it overheated (head gaskets, water pump kit, various switches, sensors, etc.)<br />I did a compression test with the throttle advanced all the way and these are the results:<br /><br />Starboard side:<br />#1 - 130 psi<br />#3 - 132 <br /><br />Port side:<br />#2 - 121 psi<br />#4 - 125 <br /><br />I shot some WD40 into the port side cylinders and #2 went to 125 and #4 to 128.<br /><br />What do you guys think? I've heard that differences between 5-10 are bad. But I've also heard that differences within 10% are ok. :confused: <br /><br />Thanks,<br />Dan
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: did compression test, what d'ya think?

Your numbers are fine. Within 10-15% (per OMC) is fine.
 

Dan Beisel

Petty Officer 3rd Class
Joined
Sep 3, 2003
Messages
76
Re: did compression test, what d'ya think?

Thanks JB! You don't know what a relief it finally is to get everything in working order! :D
 
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