Combines rotor drive sheave vibration

[aussie]

Are you sure the vibes are caused by the sheave. A common cause for this sympton is an uneven buildup of material on the backs of the thresher bars. If the RH shaft is bent a dail indicator running on the sheave periphery while it is turned by hand should show it up.

 

[bucko]

i dont think sheave is causing vibes but is an indicator of the problem. a dial guage set on outside edge confirms its not running true, just cant remember what the runout was.i feel the shaft is bent, but hoping to get some ideas before i dive in. clutching at straws cause if shes bent it will be an expensive find.