dantheACman
Seaman Apprentice
- Joined
- Aug 14, 2013
- Messages
- 31
I bought a 1987 70 hp Mercury 2 stroke 3 cylinder. I mounted it on a 1973 16' Starcraft holiday anyway I took it to the lake for a short test run 1 hour. Runs purity good alittle bit of a rough idle never stalled starts easy not has bad as I have had from other 2 stroke 3 cylinders. Before I take on a long family lake event I thought I should go threw the engine anyway I started with compression test found compression extremely low I think 82 82 78 I can't believe it runs so I got service manual all it says is 20 psi difference no specs on how high it should be but my thoughts are never below 100 psi and everything have researched the opion varies so much so I thought I would ask the experts here on Iboat. I never seen a 2 stroke with all compression low like that. What I have always seen is one cylinder go low. I checked it warm cold wot always the same I checked with 2 gauges the same. Thanks ahead of time for any responses