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Engine's RPM Seems to Fluctuate (Runs Rough)
Why does my engine's RPM seem to fluctuate (runs rough)?
Many engine performance problems can be linked to maintenance issues such as stale fuel, dirty air filter, fouled spark plug, and deteriorated oil.
A great way to help avoid these problems would be to perform an annual tune-up using a Briggs & Stratton engine Maintenance Kit.
Engine hunting and surging at idle is usually caused by a fuel delivery, air leak, or governor system problem. Cleaning/overhauling the carburetor, adjustment of the governor, and/or changing the air filer may be required.
For an example of how an engine sounds while hunting and surging, please listen to the example provided here:
For additional information regarding poor engine performance, please visit the Troubleshooting section of our website.
If you wish to perform this maintenance yourself, a good source for engine specifications and technical servicing information would be a Briggs & Stratton Repair Manual (Lookup Manual by Engine Model.) The correct Repair Manual for your model engine is often listed in your engine's .
Repair Manuals are available for purchase through our websites Learning Resources section or locally from a Briggs & Stratton Authorized Dealer.
For your convenience, Do-It-Yourself parts and products related to this and other maintenance/repair issues such as air filters and carburetor parts may be ordered through our Maintenance Parts & Accessories section.
Your will provide component part numbers specific to your engine's Model, Type, and Code that you may require.
Your best source of information regarding any engine concern would be a Briggs & Stratton Authorized Dealer. Your Briggs & Stratton Authorized Dealer has all the information relating to Briggs & Stratton warranty information, replacement engines, short blocks, parts, pricing, service/repair, specifications, etc.
For your convenience, we offer three easy ways to locate your nearest Briggs & Stratton Authorized Dealers:
Use our website's Service Center Locator.
Visit www.yellowpages.com and enter "Lawn Mowers" or "Engines-Gasoline" in the Category search field and your Postal Code in the Location search field.
Call the Briggs & Stratton Automated Hotline at (800) 444-7774. This hotline is available 24 hours a day/7 days a week and features voice recognition technology to assist you in finding the Briggs & Stratton Authorized Dealers in your area. Automated maintenance tips, product information, and FAQs are also offered through voice activated menus.
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