Mercury 65hp compression

[tbirdkidd]

After this season I just pulled and checked the compression on my 1967 4 cyl. Mercury 65hp outboard No 1 (80) No. 2 (110) No. 3 (125) and No.4 (110) the motor runs good top end and mid speed but likes to stall at idle and when shifting into gears. Should I rebuild the motor or just the carbs? If the cyl. walls checkout can I just replace the rings? Thanks for any help

 

[starcraft1982]

Re: Mercury 65hp compression

Cylinder 1 sounds like definately has an issue.2+4 also while ok,dont hit the 10%mark of 3.If youre good,then tearing down and inspecting the walls is a good idea w/new rings if walls check good.With numbers such as those,i might suspect a lean running condition,so definately do the carbs and new fuel lines all around.And for good measure,a fuel pump kit.With any luck,you wont be the first person to blow a motor next spring!

 

[JB]

Re: Mercury 65hp compression

Before you start throwing money and sweat at things that may not be broke do a decarbon treatment and repeat the compression test.

 

[tbirdkidd]

Re: Mercury 65hp compression

Thanks for the advice could you tell how to do that

 

[JB]

Re: Mercury 65hp compression

Look in the Engine FAQs Forum, tbird.

Good luck.