Is the tiny engine on her lawn mower, snow blower or out power tools making according to noises? This FAQ from Briggs & Stratton will aid you determine the problem and find solutions.

You are watching: Lawn mower backfires when shutting off

Backfire is a condition described together a loud bang, poof, explosion, etc., when the engine is to run or if shutting down. Afterfire occurs after the engine has actually been closeup of the door off. Note: Backfire and afterfire through the carburetor will not injury the engine at all!

Find the end the most common reasons and feasible fixes because that engine backfire and afterfire.

Causes of little Engine Backfire & possible Fixes causes of small Engine Afterfire & possible Fixes

Backfire generally occurs once the engine is decelerated rapidly.Common causes of Backfire:

Lowering engine rate too fastGasoline, which contains greater blends that alcoholCarburetor adjustment set too leanMuffler building and construction can induce backfireHigher than common engine temperaturesSome carburetors can induce backfire as result of the sensitivity of inner transitional passages (This problem cannot be corrected).

Possible Fixes for Backfiring:

Lower engine speed slowlyAdjust carburetor for optimum performanceInquire with devices manufacturer about increasing waiting volume come decrease engine temperature

Afterfire wake up after the engine has been close up door off.Common reasons of Afterfire:

Shutting off the engine at high RPM, causing fuel to pump with the engine for ignitionGasoline that includes alcohol has actually a tendency to ignite easier, which can reason afterfireSmall engine muffler kind and manufactureCarburetor adjustment may not be properly set for correct engine performanceAnti-afterfire solenoid may not be working properly

Possible Fixes for Afterfire:

Allow the engine come cool by idling the engine down with proper speed (15-30 seconds)Change come a different non-alcohol or alcohol brand fuelEnsure suitable carburetor adjustment because that optimal engine performanceContact the devices manufacturer for updated draft in air regulate baffling, mufflers, etc.Check the anti-afterfire solenoid for proper operation Note: If equipped v an anti-afterfire solenoid, shut engine off at complete throttle

In any event, your best source of details would be to above your neighborhood Briggs & Stratton business dealer.

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