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


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!

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?


Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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