Small Engines (Lawn Mowers, etc.)/Briggs and Stratton Engine


I have a Briggs engine that I've been working on for about five days now.  Have cleaned carb, replaced broken flywheel key, replaced spark plug, cleaned gas tank.  First it would start, then die.  Replacing broken flywheel key didn't help, but there is still a little pay there, have taken surface rust off flywheel and coil pickup, didn't help.  Put a working carb on this engine and it did the same thing, then put first carb on other mower and it worked just fine.  Back to first carb, put back on then got it running buy pulling on govener linkage, could keep it running then but it would bogg down when trying to increase speed.  It would then make some small popping noies, like it was still out of time or maybe a bad valve.  I'm at witts end hear.  I've been working on small engine mowers for over 15 yrs and have never run into some thing like this.  Even the place where I get all my parts didn't have a clue.  I hope some one does.  Thank you, Michael

What is the engine model, type and code number?

I have seen the plastic gear style camshaft slip on the shaft and cause timing issues.  Granted it was only once but it tool a while to figure out what was wrong.

Why was the flywheel key sheared?  This could be a big clue to a major problem.

If it is a push mower, then the blade adapter may have a sheared key, a crack or just be too loose on the bottom of the crankshaft.  I've seen a lot of bad blade adapters in the last 3-4 years...they make cheaper every year.


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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