I have been hearing a little scratching/hitting in the fan area on my 105, so I got looking and two bolts holding the fan guard came out, so I replaced them. That stopped the scratching/hitting for awhile, but then yesterday it came back, and the bolts were tight. But I watched the drive shaft turn as I cranked it and it was bouncing around, so I checked the vibration disks and they were tight and looked fine. So then I checked the drive shaft, and it's bent. My question is, how could this have happened, and is there something else I need to replace besides the shaft?
Thanks