Mariner Problem need help

[Mark Overfelt]

I have a 1979 Mariner 70 hp 3 cyl motor. Tested the compression and the top cyl barely registered, the other 2 cyl's registered 160 lbs. How bad is my problem. and what should I do next? Thanks for any and all help. Mark O

 

[steelespike]

Re: Mariner Problem need help

Could be simple blown head gasket or serious,<br />bad piston or worse.Pull the head and have a look around.

 

[NathanY]

Re: Mariner Problem need help

Well you can eliminate a head gasket, I just flipped through my manual, and that motor is the same as the Merc 70hp and it does not have a head, just a water jacket.