MTD riding mower won't start

16 years ago

I have a 4-5 year old Ranch King by MTD riding mower. It has a 12.5 HP single-cylinder Briggs & Stratton engine.

I was mowing grass the other day, going VERY slow because the grass was kinda high. Suddenly, I heard a noise and the mower jolted a little...then the engine started struggling so I immediately turned it off. Light smoke was coming out of the flywheel. Now it will not start. It cranks, but it will not catch. I don't think I hit anything...the blades look okay and I couldn't find anything in the yard near where it happened.

It has a new battery, purchased maybe a month ago. The gas tank is full...so is the oil. I have installed a new spark plug...though I am not sure its sparking. I have taken the plug out (kept it connected) and turned the key...it shocked me but I couldn't see a spark on the end of the plug. I can see the piston moving inside the spark plug hole, so the rod is not broken. I have tried putting gas directly into the cylinder to no avail.

Anyone have any ideas what it could be?

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Comments (3)

bill_kapaun
16 years ago
When it cranks, is it cranking "normal" speed?
IF the smoke was actually coming from the flywheel, it sounds like something in the stator/flywheel came loose. Maybe a magnet?
Sure you didn't have a drive belt smoking?
rjohmit
Original Author
16 years ago
Yeah it cranks at normal speed. The smoke (and it was very light) was coming through vents in the top of the hood...when I opened it, it was coming out of the flywheel.

I'm wondering if the timing is messed up so its not sparking when the piston compresses.
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tomplum
16 years ago
If Bill's on the money here, you could have sheared the flywheel key a good deal. It will spark yet, but the timing will be off. I think you will need to pull the shroud and inspect. You can remove the bolt that retains the flywheel and look down at the key way to check for shearing. You will need to pull the flywheel to check out the stator.