Corvair Forum

I have a late original 8409 crankshaft that the cam drive gear is positioned retarded a huge amount. The shaft key way was cut at 60 degrees retarded. Normally the #1 crank pin the balancer key way and gear key way all line up. Has anyone ever seen this happen on a stock crank??

If I understand your explanation --- it appears the crankgear has sheared the woodruff key. It's not common, but over the decades a number of Corvair folks have reported this problem. Sometimes - not always you can probe the key in the crank slot and if it's loose, then it's sheared. That said sometimes the sheared key will be tight. If your sure the crank gear has slipped, then the only way to confirms is to press the gear off AND it requires a LOT of pressure (a BIG press). Some will say you have to heat the gear before installing it on the crank, but the experienced shops say NO!! The gear heat transfers to the crank to fast during the press and then it binds up. If you freeze the crank it gets too brittle. Safest process is to press crank gear onto crank at room temperature. DON'T forget the paper gasket!!!

Years ago I picked up a few 140HP PG cranks because they were nitrided and in very good shape. Problem is the 140HP PG has the unique crank gear. I had a reputable shop press off the 140HP PG crank gears and install new manual transmission crank gears from Clark's. That when I got "educated" about heating and cooling the parts. All were done at room temperature and year later - no issues.