Bearing Designation

Have you checked the avalible GE sites? here is one for a 248 page motor catalog that might have some usefull information for you.

http://www.ge-energy.com/prod_serv/products/motors/en/downloads/SPCatalog.pdf

Thanks for replying. The catalog helps somewhat, stating that re-lubrication is required, but I still need to know the bearing size to calculate the amount of grease required and that was not available in the catalog.

Well theres always option "B". As its only a 20 hp motor, just open it for a good cleaning and inspection. Then you can get the exact deminsions of both bearings.

Actualy on somthing of this size, I would lean toward replacing them with a good quality sealed bearing and replace them as needed.

Unless the motor is a special frame, the bearing is likely a standard size ball bearing. Measure the bore, OD and race width with a vernier caliper and look it up in any decent bearing catalog/data book for a match. We used to do this all the time when I worked in a motor rewind shop. note: Most modern bearings are sized in millimeters but there are still some inch sizes out there.