To start, I had a problem at my previous, and only, job with 40 hp motors snapping the thru bolts...Determined that it was due to the brake on the drive causing excessive vibration on shut down. Changed braking speed and the problem went away.
Fast forward. Just started a new job 2 months ago. I have an idiot plumber "showing me around"." I notice a broken thru bolt on a 75 hp motor and he informs me that he replaces that bolt every 3 months or so. This drive doesn't have a brake set up, and all other components(belts, bearings, etc) seem to be ok. Can a "soft foot" problem create vibration through a belt driven fan that would cause this??
Any input would be much appreciated!