I have cleaned carburetor, changed spark plug, got new gas, and changed flywheel key and adjusted magneto spacing. The engine runs cuts entire lawn but sputters instead of running smoothly. I also put stabil in gas.
Briggs and Stratton engine runs rough sputters after it gets warm
- Thread starter jgaspelin
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Get yourself a spark tester. The type that you can watch while the engine is running. You are looking for a misfire. if one is detected, could be a spark plug problem (read years ago that champion plug considered a 25% misfire as acceptable) an ignition module problem, or also check for a shorting kill wire from the stop switch next the brake to the ignition module.
If that all pans out then time to start looking at compression, valve clearances, and possibly still a carb issue.
If that all pans out then time to start looking at compression, valve clearances, and possibly still a carb issue.
reynoldston
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As a rule when a engine starts to run rough after it warms up the first thing I look for is a tight valve. Another thing that effects a warm engine running rough is a coil going bad. You need to look for something temperature related. Cleaning carburetor, spark plug, gas, flywheel key and mag spacing wouldn't have anything to do with the engine temperature.
Any way to tell if coil is bad?
reynoldston
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As said earlier if it is operating temp related it isn't spark plugs, so maybe you should put three spark plugs into it. Now for coil the only test you might be able to do is, make sure it will throw a good 1/4 inch spark after you heat it up the coil with a hot air blow dryer. Other then that have it tested at a repair shop with the equipment to test coils.