OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines flywheel key shearing

The flywheel key on a 4hp Briggs and Stratton keeps shearing. Does anybody have any idea what to look for to fix this? Any help woould be appreciated!

Are you trying to run the motor without the blade plate on?
If so you will continue to shear the flywheel key.
If the boss on the blade plate has movement in it shear as well.
I hope that this will help.

Regards,
Bruce

I have found this a common problem with 4 hp B@S motors with the alloy key. I always clean the crankshaft taper and the inside of the flywheel and the key with lacquer thinners to remove any trace of oil, no more problems. You must also make sure the retaining nut is very tight.
cheers,
Wal

I have found this a common problem with 4 hp B@S motors with the alloy key. I always clean the crankshaft taper and the inside of the flywheel and the key with lacquer thinners to remove any trace of oil, no more problems. You must also make sure the retaining nut is very tight.
cheers,
Wal