Small Engines (Lawn Mowers, etc.)/flywheel key shears


I have a Troy Built OHV 17.5 Briggs & Stratton. I reacenly bought from a man who had it setting for about a year. The machine is only about 3 years old. After I got it to run it would only run at high speeds. I cleaned the carb and reinstalled it. Now every time I try to start it the flywheel key will shere and it will be out of time. I never came across this problem before and don't know how to fix it. Hope you can help. Doug

Did you unscrew or remove the governor arm?  If so you will need to follow the static setting of a mechanical governor.

One trick I have used in the past is to use some fine valve grinding compound on the crankshaft taper and flywheel and lap the flywheel to the crankshaft.  Is there a washer under the flywheel nut that may be cracked.


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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