Small Engines (Lawn Mowers, etc.): Toro Z Master

Question
I have a Toro ZMaster model 74903 mower.  After using the mower for about an hour the engine cuts off.  If you wait about 20 minutes the engine will start back up.  Tried 3 different repair shops with no success. Replaced fuel lines, fuel filter, carb adjusted, and coils tested ok.  Please help!

Answer
Did you try a new or different brand of spark plug?

Have you been able to verify if the ignition is still producing spark when it stops?  I would purchase an inline spark tester.  I'd recommend ordering the Briggs & Stratton 19368 Ignition Tester.  I have had very good success with identifying faulty ignition spark issues with this model of tester.

Do you have a Kohler model CV730 engine?

Eric