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J.R., Small Engine Technician
Category: Small Engine
Satisfied Customers: 7445
Experience:  Owner of outdoor power equipment business, repairing all makes and models.
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I have a lawn tractor with a 21 HP B&S Vanguard engine. It

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I have a lawn tractor with a 21 HP B&S Vanguard engine. It has recently developed a rough running problem, spitting and popping blowing black smoke particulary at full throttle. I have changed the plugs and air filter, still the same. Any suggestions?
The problem may be a plugged up jet in the carburetor. I would take the carburetor apart and clean it and then put it back together with a rebuild kit.
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Customer: replied 6 years ago.
should there be a number on the carburetor to use in order to get the correct rebuild kit?

Look on one of the valve covers for all of the model and type numbers. Go to and enter those numbers. It will bring up a parts list that will give you the correct part number.




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