Bicycle Mechanics - Cleaning a Freewheel

I bought a used 6-speed freewheel for my rebuild project. It's in great shape but not very clean.

I'm thinking it might not be the best idea to soak it in degreaser, but that I'd be better off scrubbing it down with a cog brush dipped in degreaser. Any suggestions?

I'm thinking it might not be the best idea to soak it in degreaser, but that I'd be better off scrubbing it down with a cog brush dipped in degreaser. Any suggestions?
Works for me.

Spray it down with your favorite degreaser. Scrub it with a stiff brush to loosen the gunk, then take a rag and hod the edge tight so you can slip it up between the cogs and work it back and forth.

While you're at it, drip some motor oil into the gap between the cogs and the body to lubricate the pawls.

Old tee shirts make good freewheel cleaners; old socks aren't bad, either.

Most freewheels are trouble free through their lifetime; if it's working then just clean the gears with a solvent, that's pretty basic.

If the freewheel is not working properly then you can try to fix it but do not pour oil into the freewheel to lube the inner workings (otherwise you will force dirt and grit into the freewheel!) without first soaking (submersing) it in solvent working the mechanism back and forth a bunch of times then let soak overnight, next day shake it and drain it of the solvent and either let it set in the sun for a day or blow it out with an air compressor, Also if you do by by some odd chance decide to soak it in solvent, after it dries use a fast evaporating carrier base oil like Speed Skate Lube to relube with and again work the mechanism a few times then let it dry for about 12 hours.

Some freewheels, like Sachs are sealed and do not like being messed with. Most are unsealed and you can flush out dirt with a solvent, then drizzel in oil. I put stuff in the wide (big cog) end and let it drain out the narrow end. I use WD40 as the solvent, it seems to work well.

All the Sach's I've ever seen are indeed sealed, BUT they have a lube port where you can inject more lubrication into it if needed-which is rarely if ever-which is true with most freewheels anyway as far as rarely needing lubrication, usually the freewheel gears wear out before you need to relube.