Small Engines (Lawn Mowers, etc.): john deere L110 kohler 17.5 hp cv491s 27509, john deere l110, fly wheel

Question
My mower runs, but hard and sometimes misfiring.  It almost sounds to fire too soon, but I do not know.  It does shake and it did not do this last week.

I have replaced the plug and coil.  I have taken the cover off the top of the flywheel and can barely see the shearing key b/c it looks low when I look in the slot. Could a slight shift in the flywheel cause this? I cannot pull off the flywheel with my hands.  Since I have enough power to cut and pull aerator up hill, hard to think that fuel or  compression problems. Reading from your suggestions to others I did look at the parts drawings.  Could the regulator be a problem?

Answer
yes the flywheel key way can be partially sheared causing the mower to be slightly out of timing. My rule of thumb is when in doubt change the key. When you have torn it down that far your only a few minutes away from changing it, at a very low parts cost. And no you won't be able to remove it with just your hands, it requires a fly wheel puller. Sometimes you are able to thread the nut back on just to the point that the top of the nut is flush with the crankshaft threads to not damage them, then giving the nut a few sharp blows with a hammer while having EVEN pressure on 2 sides of the underneath of the fly wheel with 2 screw drives, usually requires another set of hands........Does this model have a fuel pump, have you checked it? Fuel filter? I think your looking in the wrong direction, 95% of all small engine failures are usually fuel related.......Tom

Could you be so kind as to go back and have them change that which they will do, it really dropped my ratings down badly. I always true my best to help eachone, and all we get for it is our ratings....Thanks, Tom