Leon Speed

...don't!!!

Or be prepared to have very noisy bearings

Better to replace the bearings and carbon brushes.

jpitman2

Mate of mine used compressed air to blow debris out of a laptop cooling fan...blew the fan completely to pieces. Boss's daughter was not pleased..
Use such air with care.
jp 83 Euro S AT 55k

Landseer

Drilling a little hole just over the upper bearing and oiling it a little bit can extend the use of it.

M. Requin

Never ever ever ever spin a ball bearing with compressed air. In a second or two that bearing is ruined. Drilled into me in a machine shop I worked in when I was in college. Instead of the inner or outer race driving bearing rotation, the air forces the ***** to skid around the races- instant galling, instant end'o'bearing.

DKWalser

So, you're saying it's a bad idea?

Seriously, that's good information.

dr bob

Drilled into me early was the same recommendation David shares. It was a too-common practice to use air to spin-dry tapered roller bearings like wheel bearings. There was no loading on the caged rollers, but always the risk of something in there damaging the rollers or inner race. Something loose inside could cause the cage and rollers to grab, severely damaging the fingers that were holding them. It's OK to use air to flush out any remaining debris and cleaning solvent, just do it axially so the rollers or ***** don't spin.

One step further, there are cavities in the rollers and cage that will hold cleaning solvent, and risk reducing the new lubrication as it leaches out of those cavites in normal service. There's a very good case for not solvent-cleaning roller bearings at all. Pushing new grease through will remove the old stuff. If you are worried that there might be harder particles remaining, replace the bearing with new; those harder particles have already damaged the bearing.