From the details you have provided the Kohler Crucifer engine has become possesed by deamons.
You will have to push it into the middle of the yard and at midnight on the eve of the solstus dance naked around the mower while sacrificing your youngest daughter to the mower gods.
or it might be a simple problem that is easy fixed but from the descriptions you have given only a gypsy soothsayer would know.
Engine model number, mower model number and description of what happens as it you were talking to a deaf dumb & blind person who has never seen a lawn mower in his life and we might be able to help.
