1975 70hp Evinrude water in #3 cylinder

[terswan]

I've got a 1975 70hp evinrude that has been running fine. I was going down river at wot it "poped" and lost power I brought it back to idle and it quit. Got it restarted running really rough. Once I got home and started investigating its got water on #3 cylinder. Any suggestions on how to diagnose this problem? Possible causes? I am a mechanic (heavy equipment and trucks) however I don't know much about outboards. Thanks in advance for any help.

 

[tx1961whaler]

Re: 1975 70hp Evinrude water in #3 cylinder

Compression check first, then pull the head to inspect if the compression was shown to be low. If the piston and cylinder look OK, then put a new head gasket on and recheck the compression. If the piston is toasted, then you've got some decisions to make......

 

[tashasdaddy]

Re: 1975 70hp Evinrude water in #3 cylinder

hope you only have a blown head or exhaust gasket.

 

[terswan]

Re: 1975 70hp Evinrude water in #3 cylinder

I did A compression check all three cylinders had 125+

 

[R.Johnson]

Re: 1975 70hp Evinrude water in #3 cylinder

The water is most likely coming through the exhaust cover gasket, not uncommon on the inline 3 cylinder. Pull the head, and replace that gasket also, and check the cylinder bore's

 

[00ferret]

Re: 1975 70hp Evinrude water in #3 cylinder

I have/had exact same problem. It is probably the exhaust gasket. I recommend getting a friend to help get to it. It takes a little elbow grease to get to the last couple bolts at the bottom otherwise you will end up taking out alot of screws you dont need too (found this out too late). With mine you could easily tell where it had been leaking. Its about a 50 dollar fix (if you replace the other gaskets which are probably not in very good condition considering the year) so not too bad considering the other option of a new motor.