I had a new Brock bin fan that was slow to start.  Even had the dealer come look at it to see why.  They didn't find anything but some time later (couple years, I think) it finally quit on my so I pulled it out to see if I could fix it.  First thing I looked at were the capacitors in the motor.  One of the capacitors was completely out of the wiring system as both of the leads to that capacitor were fastened to the same terminal on it.  Don't know how that affected the motor but it must have been a start capacitor as it started so slow.  Anyway I had to buy a new motor even though it was bad from the factory!

Edit to add:  Mine was a Baldor motor also, 15 hp single phase