Small Engines (Lawn Mowers, etc.)/lawn mower


i had a tune-up done last year on my sears riding mower. everything seemed fine for a while then the mower would stop after about 20 min. sometimes i could get it restarted right away and then sometimes i ould need to wait about an hr or so. it should not do this. any ideas... fuel pump?

These are the toughest problems to fix.

I would start by purchasing a new spark plug(s).  When the mower stop, hop off the seat and change the spark plug when it refuses to restart.

Some odd things I have run into over the years that can cause you problem:  

Gas cap not venting...vacuum forms in fuel tank and will not allow fuel out until enough air enters tank

Electric fuel-shut off solenoid closes when it get the engine heats up and stops gas from entering the engine.

Some safety switch or switch connecting not properly working when hot...this one took me several weeks to fix as the problem did not happen very often...when the connection failed is was the same thing as if you got off the seat and the engine stopped.

All of the above are rare but I've had them happen so I always check when a customer has a similar problem such as yours.

Do you have to be mowing for the problem to happen?

Can you drive the mower for more than 20 min and not have the problem?

First thing to isolate is to verify if you have a spark or fuel problem.  Do you have an inline spark tester to verify you have spark when the mower stops?


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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