Small Engines (Lawn Mowers, etc.)/RX75 Carb


It would not let me ask a follow up question but I cleaned the carb again and it is still happening. I decided to spray carb clean around the carb by the gaskets and when I do it runs fine. Could it be a vacuum leak possibly.

Yes, an air or vaccum leak.  If my memory serves me right there is a brownish piece of plastic between the carb and engine.  It is an insulator to reduce heat transfer and there are 2 gasket, one on each side.  It is possible a gasket it leaking or the insulator is warped.

If you don't have new gaskets you can make some or you can try something like Permatex number 2 non-harding.  The Permatex will work for a while but odds are heat and vibration over time will cause the non-harding type to squish or wiggle out.

You can buy gasket making material at many auto parts stores.  Not too difficult to make but it takes some practice, patients, and time.


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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