Originally Posted By: bankbum
You can take a shields off and soak the bearing in wd40. It may help. It has helped in the past on gritty bearings

This ^^^
I take the shields off and use WD40 (with the tube) to flush (blast) the bearings.
There is a thin snap ring that holds the shields in place. I use a hook point to grab one end of the snap ring and work it out.
The shield comes out easily after that.
In the pic below the snap ring end gap is at 11:00..



When you think think bearing is clean, put it on a sharpened pencil and spin it.
Listen to it...you will know when it's clean.

You are not supposed to expose bearings to compressed air, but I hit them with canned air sometimes.
Just don't spin them up to 25,000 RPM and you'll be OK.

So, pull the shields, do a thorough cleaning and I'll bet that the gritty sounds go away.

Edit:
I do like to soak them in Coleman fuel or similar.
I'll swish them around in it.
Wash the all WD off or Brewer will nag on you.
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