Chainsaw Repair

Could have been a casting flaw in the flywheel.  It also could have been damaged by being whacked with a hammer or dropped onto a concrete floor sometime in the past.

There were a few old Echo models that experienced FW failures.  One is the CS1001VL if I'm not mistaken.  More than a few of them have grenaded the FW.  I know a guy in Pa that has that model in his collection.  The FW blew a while back.  Thankfully, nobody was hurt.

Another Echo model with FW issues was the CS500VL.  There were so many problems that Echo had a recall of the saws.  If your 500VL fit within a certain SN range (mine is after it......dangit), they'd give you a new saw to replace it. In the wording of the recall, they blamed improper R/R of the FW during breaker points service (by homeowners, or improperly trained mechanics).........causing damage to the FW that could later result in a blown FW. 

The 500VL's after that SN range have a stronger FW (and possibly a different crank/FW taper....cannot remember now).  The 500EVL (electronic ign) saws are also not affected by the recall.  Recall is dated 1986 or so.