Is the solenoid clicking and trying to start?
IF so AND IF it's a Briggs OHV engine, adjust the valves.

Edit-
Apparently these have a Kohler, so describe what happens when it doesn't crank.
IF the starter just spins, the ring gear on the fly wheel is bad.

This post was edited by bill_kapaun on Wed, Apr 17, 13 at 10:20