compressor motor, sealed bearings, what's the grease fitting for?

[shannonw]

Hi all, cleaning up this older baldor (probably about 15 years) i'm confused.

the bearings are sealed but the end caps have grease fittings. I was going to reassemble it after painting the motor and cleaning and painting the end caps. I was also going to add some grease to the cups but i'm not sure if i should or how much?

Not sure i understand the reason for the zerks if the bearings are sealed?

Any ideas? Thanks for any help

 

[shannonw]

looking again, i guess this is just to lube the end of the bell housings a bit, so i just lightly added grease where the zerk would have put them. Since it's sealed doesn't look like it would need much so i didn't go overboard

 

[Kevin C]

Those look like shielded bearing, not sealed bearings. There should be a small gap in the shield. Not sure if that's hows its done, I have never had a greasable motor apart.

 

[shannonw]

Hi kevin, thanks, yeah i'm wondering myself now, i only see shielded in the diagrams

http://www.ntnamericas.com/en/produ...h-results/datasheet?pid=80770&cid=RBSRD&ctc=B

maybe you're right and it's shielded, not sealed, there is a small gap there.

 

[shannonw]

yeah i think you're right from some googling (not a bearing expert). they seem pretty well greased inside so i'll just fill the grease cup (where it would be filled anyways if i greased the zerk before i finish assembling

 

[shannonw]

yep was shielded. it was just a tad noisy spinning the bell. i was able to press grease though the (shield i guess). spinning the hub sounds better now. So the zerks fill the bell cavity and push the grease through that thin gap/shield.

 

[Mr onetwo]

Go to Baldor's site and find your motor number.It will list the bearings in the build spec.I just rebuilt a farm duty 5HP Baldor and the bearings in it were wrong.The specs called for a bearing with a shield on 1 side.It goes toward the motor side and the open side faces the bell ends of the motor.That way when you inject grease thru the zerk it fills the bearing without getting to the electrical parts.