9.8 2-stroke, Raw water spraying out top of motor

[fortunate2001]

Taking a slow dingy ride yesterday, and the motor starts bursting thrust for a split second, then gone, then again, then gone, no one touching the throttle. I think maybe one cylinder is firing, then not firing. I take off the motor cover, and find a small fountain of raw sea water shooting up from the engine. Closer look, there is a tiny hole on the top (see picture). Salt water has been spraying around in there for who knows how long (maybe a day or a week). I shut it down, poured a couple bottles of fresh water on it (just because that is what I had), and let it dry in the sun for a couple hours. Then I plugged the hole with some marine-tex, and gave it a few more hours to set. End of the day, tried the engine again, but still running poorly and stalling at lowest RPMs.

Tomorrow I will start to troubleshoot. I can see the metal on the outside of the plugs is already corroded, so probably more trouble to be found in the wiring. What should I inspect? Test? Should I try to do a better cleaning out than just the fresh water rinse?

​TY.

 

[Sea Rider]

That engine looks horrible badly taken care of. You have a rotten upper water plug and in a short term expect same on lower plug too. Cyl head has 2 at both sides, the lower is not visible. Will need to get same size water plug at an auto store as Tohatsu doesn't sell them as spares. That's product of corrotion, salt, engine was badly or not flushed at all specially if used on saltwater,

Other faster alternative, sand upper water plug evenly and apply a thick coat of epoxy cement on top plug and plug surrounding. Let dry 24 hours.

Happy Boating