Cub alternator

[oldcub]

I replaced the existing alternator on my Cub with a 20-102-1 (Lesters 2117) 63 amp one wire alternator from Nations Starter/Alternator. When I kick up the rpm's a little to excite it and it starts charging, it makes a loud high pitched rubbing noise. Putting a sounding rod on it doesn't indicate any of the bearings a bad. I am thinking the shaft has flexed enough to make the fan rub the housing when it is loaded. Any suggestions besides spending more for a Delco?

 

[DJ54]

Did you use the same belt..?? If it has been on there a while, and a bit dry, it may squeal a bit like a bearing. If it's in the wide open, you can take a bar of soap, and rub on the belt when it's running at idle. Or, just a spritz of WD-40 on the belt will make it stop for a bit, to let you know for sure, if it's the belt, or something else.