Crankshaft pulley jumped off the crank, help!

[ridemore]

I cranked the car (’85 190E) and there was this engine noise that suddenly grew louder. Next thing I knew, a loud crash of metal, after which I cut the engine off and investigated. It turned out that the crankshaft pulley had come off the crankshaft. The crankshaft belt pulley and vibration damper came out together as one piece (still coupled together by all those bolts). The big center bolt and 3 washers are still screwed into the crankshaft. There seem to be some kind of black rubber that failed and caused the pulley and vibration damper to separate from the crankshaft. Good thing I was idling in the driveway.

Does anyone know what the fix for this is? How do you hold the engine steady to remove the 27mm retaining bolt? On the Hondas, I would remove the starter and jam the flywheel with a big screwdriver. What’s the procedure for the 190E? Do I need to buy the belt pulley and vibration damper together, and just remove the big bolt and whatever is left from the old pulley, then swap in the replacement and bolt up? Please help.