what compression should a 1957, qd-18, 10 hp johnson have. i can only get 30psi. thank you
S smyers1115 Cadet Joined Sep 20, 2007 Messages 11 Sep 20, 2007 #1 what compression should a 1957, qd-18, 10 hp johnson have. i can only get 30psi. thank you
Chinewalker Fleet Admiral Joined Aug 19, 2001 Messages 8,902 Sep 20, 2007 #2 Re: expected compression By any measure, 30psi would be low - UNLESS your gauge is not seated properly. Ideally, I'd like to see at least 85 psi in each cylinder, with a less than 5% variance between them... - Scott
Re: expected compression By any measure, 30psi would be low - UNLESS your gauge is not seated properly. Ideally, I'd like to see at least 85 psi in each cylinder, with a less than 5% variance between them... - Scott
