Question about Ariens 21 In Classic Walk Behind Push Lawn Mower ()

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Ariens self propelled hit a rock will not start clanks and smokes Crankshaft does not seem to be bent. Somtimes kicks back when trying to start.

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If you have kick back or the mower backfires you probably have a partially sheared flywheel key.

The good news is they are cheap and designed to shear to protect the motor from damage.

You can take the recoil cover off the engine and then remove the nut that holds on the flywheel and gently pry off the flywheel.

You should see a mangled flywheel key that was under the nut holding the flywheel on. Take it to a mower parts store and match it up with a replacement. Put the new one back in and reinstall the flywheel.

That should do it! Good luck and be careful!

Posted on Aug 24, 2010


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Please take time to rate me

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