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Small Engines (Lawn Mowers, etc.)/motor only runs at full throttle


QUESTION: Ok so i got a Go kart the other day for free and the motor didnt crank at all. So i cleaned out the carb and made sure it had fresh gas. I got it running but it will only crank and run when its at full throttle. When i let off throttle it stalls and cuts off. I was thinking a gasket somewhere. What do you think the problem is? Thanks! Tyler

ANSWER: What engine do you have?  It sounds like the low speed carb circuit is still dirty.  I need to know the engine brand along with the model, type, and code/serial number to know what you are working on.


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QUESTION: Im at school now in class but i know its a Tecumseh 6.0HP Power Sport motor. I can get the serial number this afternoon if you really need it. Thanks!

One of these links should be the engine repair manual:

First I would check the throttle linkages and make sure you can move the carburetor butterfly shaft by hand.  It should move freely and easy.  

Second I would perform a static governor adjust to make sure the governor system is properly configured.

If the engine still runs at full throttle only the governor spool or weights may be bad.  I have seen several Tecumseh engine with defective governor spools/weights.

Perform the first two recommendations and let me know what happens.

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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