1998 johnson 150 ocean runner (knocking)

[Beacher11]

my engine has a knock and skips at lower rpm's. I recently changed the plugs thinking it would solve the problem...still running rough. Engine has been great and has 1400 hours. No real complaints except the knocking that recently started...I overheated recently but shut it down immediately and let it cool. Is the knocking related?

 

[Jayrock]

Re: 1998 johnson 150 ocean runner (knocking)

I had the same problem with my 1996 Evinrude 200. Do a compression test. it will answer a few questions... if the compression on any cylinder varies by more than 10% pull the head on that cylinder and have a look.

 

[dehydrated]

Re: 1998 johnson 150 ocean runner (knocking)

is it at wot or all through rpms could be piston slap i agree compression check will tell the story