Briggs and Stratton 16.5 hp. Crankcase cracked. Was curious to find out what happend so i took the engine apart. The counterweight link was in a million pieces. The rest of the engine looked great. Anyone have any idea what happend?
Do you have pictures?
Sure, the bushing in the link attaching the counter weight to the eccentric on the crankshaft wore out and the play created resulted in a hammering action which finally resulted in the weak point, the back side of the link breaking and sending the counter weight into the crankcase casting knocking a hole in it.
This happens with age but also from poor lubrication discipline, abuse.
Walt Conner