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HomeRepair HelpBriggs & Stratton RepairBriggs & Stratton Small engine runs poorly Repair
Briggs & Stratton Small engine runs poorly
When your Briggs & Stratton small engine runs poorly, runs rough, surges, sputters, or loses power, the carburetor is the most likely cause. A carburetor clogged with varnish from stale or ethanol-blended fuel left in the carburetor can restrict fuel flow and make the engine run unevenly. Clean the carburetor with carburetor cleaner first. If cleaning does not restore proper operation, the carburetor may need a repair kit or complete replacement. Next, inspect the spark plug for a cracked porcelain insulator, burned electrode, heavy carbon buildup, or no spark with a spark plug tester. A worn or defective spark plug can cause an engine running rough condition and should be replaced when damaged. A clogged fuel filter is another common cause, especially when old fuel has been left in the fuel tank. Drain the stale fuel and replace the fuel filter. Enter your model number to find the exact Briggs & Stratton carburetor, carburetor repair kit, spark plug, or fuel filter for your specific engine.
01 - Briggs & Stratton Carburetor
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the engine for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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02 - Briggs & Stratton Carburetor Repair Kit
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the engine for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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03 - Briggs & Stratton Spark Plug
Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.
Highly Likely
04 - Briggs & Stratton Fuel Filter
The fuel filter might be clogged. A clogged fuel filter is most commonly caused by leaving fuel in the engine for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the fuel filter and cause the engine to run roughly. If old fuel was left in the engine, drain the old fuel from the fuel tank and replace the fuel filter.
Less Common
Frequently Asked Questions
Why is my Briggs & Stratton small engine running rough or surging?
What should I check when my Briggs & Stratton engine runs poorly and loses power?
Can an old spark plug cause a Briggs & Stratton small engine to sputter?
How do I find the correct replacement part for my Briggs & Stratton small engine?
What should I do if my Briggs & Stratton engine still runs poorly after cleaning the carburetor?