Flywheel stuck and un-stuck, what next?

[Bellabella]

My 2002 Tohatsu 40 hp suddenly just stopped with no prior warning last week. I've had absolutely no issues with it for the 5 years I've had it. Turned out the flywheel was stuck for some reason, so I removed the plugs and sprayed some lubricant into the holes and marinated the flywheel in lubricant too. I let it stew for a few days and then rocked the flywheel back and forth - eventually it started moving easily again. Now the engine starts nicely, but I haven't let it run for long at all since my father-in-law (who actually knows something about engines - unlike me...) said it'll just get stuck again and talked about pistons and connecting rods snapping and possibly flying about.

Just before the problem I had been fiddling with the gear and throttle cables because the throttle was a bit stiff, don't know if and how this could be related to the flywheel issue.

Any ideas what the issue might be here? Is it a risk to have the engine running?

 

[pvanv]

Is your actual model M40D, or MD40B? (Is it a TLDI?). If you ran without oil, that could cause the motor to get stuck. Also, a severe overheat could do that. Now that it is free, you should be OK, as long as you are lubricating OK.

 

[Bellabella]

The model is M40C, not sure about the TLDI bit, but it's 2-stroke for sure.

I doubt that I ran without oil, I've certainly never forgotten to add it before...

 

[Sea Rider]

How old is that horese ? was it used lightly, severely through the years ? Does the motor makes a notorious audible sound when running through the throttle range ?

Could have crankshaft bearing issues on their way to become kaput. If runs good use it, just add the right amount of 2 strokes oil with fuel for a neat 50:1 mix.

Happy Boating