1990 Mariner 2.5 Overheating?

[Wildspirit]

I have a Mariner 1990 2.5 hp. outboard that stopped after running it wide open for 10 minutes.

I bought it used but didn’t use it until the last few months. During that time it got progressively harder to start. Sometimes flooding – sometimes a dry plug but not starting. So I cleaned the carburetor and took it out for a test run. It ran smoothly at idle and full throttle, although at first there was a lag in between when I move the throttle lever and when it accelerated.

I always ran the engine at low revs, but this time I ran it wide open and it quit right after I saw a few whisps of smoke. I noticed the shaft felt hot. It wouldn’t start but I let it rest 10 minutes and than it started. Ran for 3 minutes more and then quit. I did notice that water was running out of the 3 holes in the top of the shaft so I think the water cooling is working.

I tried to start it an hour later and it didn’t start.

Does anyone have any ideas what is wrong with it and how to fix it?

Any suggestion would be most appreciated.

 

[timguy]

Probably damaged from overheating, but do a compression test first. It may have just lost spark from something melting. If compression is okay, you can likely fix it without too much expense. If compression is below say 60 psi, then it may need more extensive repair. Evidence of water flow is not always assurance of "complete and adequate" cooling.