Super confused by motor bushing design

[JackBauer]

Hi folks.

My first post here - I'm doing motor repair and have a couple questions. The motor is a 1/10 HP electric motor for an Austin Air HM400 HEPA filter. While it is a high quality unit, their support sucks... E.g, they use proprietary hardware you can't just buy a replacement for and they will not sell you parts - they make you ship the darn thing back to them.

Anyway - the motor problem I originally thought might be a run capacitor problem, but after replacing that, with no avail, and realizing the motor rotor will not spin very freely at all, I thought it was time to take the motor apart and check out the bearings. The rotor shaft is mounted vertically. First up is the top motor shell:

[img:left]http://postimg.org/image/pf1ubs22r/[/img]

The rotor: (About 8" long total) (The "down" direction in the picture actually points up in the filter)

[img:left]http://postimg.org/image/4w619nuhj/[/img]

And finally the bottom part of the motor casing:

[img:left]http://postimg.org/image/rvcuh3ywz/[/img]


What I can't figure out - is what the heck those little "cotton" like shavings are doing inside the bushing... Seen best in the first picture. Note that the first picture is showing the top half of the motor flipped upside down. Normally those little cotton like thingies are somehow held in place even when that casing is flipped over. Granted the shaft has a collar on it, but it is not as wide as the opening to the bushing area. Not sure if this is making much sense - it's a bit hard to explain.

1) So can anyone help me understand what those things are - that are in both the upper and lower bushing enclosure within the upper and lower motor casings?

2) The motor was somewhat seized - but after cleaning it and the inner cylinder of the bushing, it will spin more freely - but before I re-assemble, I want to determine what to lubricate it with. Any advice?

Thanks

 

[The_Eric]

That material holds an oil to later be absorbed by the bronze bushing to lube the bushing/shaft.

 

[djb]

The cotton is likely the remains of packing yarn, designed to retain oil for the (probably sintered bronze) bushing.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2860202

 

[JackBauer]

Thanks guys - ironically that was the post that initially led me here when I was looking for lubrication for this small motor.

A friend of mine suggested that maybe it was used for lubrication but I just didn't see how both the top and bottom bushing would be able to absorb it from what appears to be a round "valley" around the bushing.

Incidentally the bushing appears to be some sort of steel alloy. The color does not appear to be any shade of bronze. Also I just looked and the bottom bearing cotton thingies seem to be moist while the ones on top, with the bottom "open"... Well gravity, time, and the spinning, seem to have all colluded to have all lubricant lost.

I still am not entirely certain which lubricant to use as there was no conclusive answer in that other post.

 

[ac_tc]

thin oil that doesent smell bad..

 

[tom slick]

There are bronze sleeve bearings that have a high iron content (SAE 863 "Super Oilite") and are silver colored.

 

[Rick in PA]

I've got a little can of 3-in-1 oil for electric motors that is SAE20 but the can lists "For 1/4HP or larger". So I'd say something lighter than SAE20. Perhaps a good old fashion hardware store can help. I keep a bottle of sewing machine oil around for the odd jobs. Sewing machine oil is very thin and highly refined, for delicate machinery. Just a couple of thoughts...

 

[morris]

here is a point of history. chrysler invented the oli-lite bushings. " Oilite was developed by Chrysler in 1930,[1] originally for use in bearings for water pumps and spring shackles." http://en.wikipedia.org/wiki/Oilite

 

[dirtymudder]

You want to use a non paraffin based oil. Most of the time it comes in a 4-6oz plastic bottle with a 8-10 extension tube on it.