You are here:

Small Engines (Lawn Mowers, etc.)/mountfield lawn mower engine poor running


Dave wrote at 2013-04-16 09:12:40
i have had a engine mechanic look at my mountfield sp414 rs100 engine and the carburator is drawing in too much air it was fixed by making a new gasket with a smaller hole now not hunting any more runs fine  

Lannin the mower man wrote at 2016-05-18 22:54:40
I had same problem it was the jet on top of the carbretor on mountfeild rs 100. The two plastic screws its the bottom one.below throttle adjuster and make sure you clean jets each side of  carbretor were airfilfer goes on.hope it works out for you like it did for me.

Small Engines (Lawn Mowers, etc.)

All Answers

Answers by Expert:

Ask Experts


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

©2017 All rights reserved.