low compression 30 hp bigfoot

planetech

Cadet
Joined
Jun 6, 2010
Messages
7
Working on a 30 hp mercury bigfoot with low compression in the #2 cylinder. #1 reads 110, #2 reads 65 and #3 reads 105. Any Ideas on the low one? I am thinking it could possibly be a head gasket or valve adjustment. I am going to borescope the cylinder wall tonight and look for scoring. Any help would be appreciated.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,931
Re: low compression 30 hp bigfoot

Ouch!!!! Your on right track, look for head gasket blown,scoring or cracked head/valve seat.
 
Top