Small Engines (Lawn Mowers, etc.)/B&S Carburetor


A friend has a pressure washer with a B&S engine. It was not run for three years and would not start. I figured it had "varnished". I cleaned the tank and carb. (which did have varnish) and replaced the needle valve and seal in the carb. It started right up but did not run right - when the load was removed (pressure washer trigger released) the engine stalled.  I took the carb out and found that the seal was not seated. I got it properly seated.  This time it ran great. We used it for about 20 minutes when it stopped and would not start. It will run if gas is sprayed directly into the throat of the carb. There are no adjusting screws. There is a bolt that holds the gas bowl to the carb. This bolt has a tiny hole at the thread end (bottom) and two tiny holes 180 deg. apart on the sides between the threads and the bolt head. There is a "U" etched into the head of the bolt. It looks like gas has to go through the side holes to the end hole to get to the engine. All thee holes are clean as is the needle valve opening.  The bowl does fill with gas. Is there an adjustment on the bowl bolt (with the "U")?  If not, what else could it be?  Thank you.

No adjustments.  There is a clogged passage/orifice in the carb.  Remove and dis-assemble carb again.  Blower compressed air from an air compressor through the carb orifices.  Re-assemble and re-install.  You might want to use some strong carb cleaner, Berryman or Valvoline, to help clean the carb.


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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