Thermal Runaway

[D.W.B in Atoka]

I have a 1999 50 h.p.Merc tracker.I was running it on the muffs in the drive.The muffs came off and I didn't know it.When I tried to turn it off and it took off. Could not kill it.I even pulled the plug wires.I pulled it away from the house because I was afraid it was going to blow up!All I could do was watch what I thought was going to be a melt down.It finally stopped.After it cooled down I pulled the plugs and turned the fly wheel and it turned.Replaced plugs and impeller of course and it ran!What other damaged may have I caused and has anyone heard or experienced a motor actually surviveing such an abuse? Thanks for any and all information.<br />D.W.B in Atoka

 

[bubbakat]

Re: Thermal Runaway

running away like that can cause a lot of different damage like scored walls, bent push rods, holes in pistons, just a few to mention. a runaway is caused by the heat cooking off gas that is getting to the cylinders it like a diesel engine it makes its on fire, you may have gotten lucky I would do a compression ck to start with and pull heads to check Cly walls. But i usually go overboard when i ck stuff any way

 

[roscoe]

Re: Thermal Runaway

For everyone future reference.<br />The quickest kill is to hold hand or rag over carb(s)/ air intake.

 

[bubbakat]

Re: Thermal Runaway

Thanks rosco no air no burn