Originally Posted by
jackbombay
Freewheel maintenance! What can I do to it? What should I do to it?
Don't take it apart! I have done it, it's not impossible, but it makes a "can of worms" look clean and simple by comparison. Just oil it.
Grease is usually bad on freewheels -- it can prevent the ratchet pawls from clicking back, leading to partial engagement which chips or shatters the ratchet teeth and/or the pawls.
Your freewheel is missing the seal on the back side. It just presses in lightly, and can fall off. That's why you can see the balls, those are hidden when the seal is installed. Not ideal, but not a deal-breaker either -- you may just have to oil it more often because of the easier ingress for dirt, water etc.. Over-oil it, then set it on a rag to let the excess oil drain out, and that's usually enough cleaning.
The seal on the front side can be removed too if needed for cleaning, like flushing it out with solvent. Just get something thin under it, like the tip of a pocket knife. It's a very light press fit.
Mark B