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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 29879
Experience:  Service manager and technician for all brands of engines with 40 + years of experience.
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Curtis. I have a Briggs and Stratton Classic 35 on my Sovereign Self Propelled Lawnmowe

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Hi Curtis. I have a Briggs and Stratton Classic 35 on my Sovereign Self Propelled Lawnmower. Lately it lack s power, the plug soots up and seems to have problems driving the mower when gearbox is engaged - only working intermittingly. Any help would be appreciated.
Jim D.
With the spark plug sooting up, it is not getting enough air. Is the air cleaner element clean and open? Could the choke butterfly in the carburetor not be opening fully? What is the engine model number? Example(###) ###-####B1
Customer: replied 2 years ago.

Hi Curtis,

Apologies for delayed response to your email. I only managed to find time to look at the mower again yesterday. i cleaned the air filter (bit oily) and refitted. The engine runs a bit smoother now but I still have the intermittent drive problem. Sometimes it works and most times it doesn't work. When I engage the handle, there can be a delayed reaction or none at all. sometimes if I move the machine back and forward then try again, it works but as soon as I stop or release the drive handle I have to go through the same process all over again. I checked the gearing under the rear wheel hubcaps. They appear in good condition. I also tried adjusting the cable. This made no apppreciable difference either - probably worse. Wondered if you have any ideas?



The drive is belt driven by the engine. Have you looked at the drive belt to see if it is loose?
Customer: replied 2 years ago.

Hi Curtis. Drive belt is new and tight enough to drive.


Gearbox problem. May not be shifting inside. I would remove the cover and look.
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