How to Remove Blind Bearings with a wet Paper Towel

[IAMSatisfied]

It's fascinating what atypical materials can serve as thick hydraulic fluid... I just removed a pilot bearing while replacing my clutch and used white bread to the same end (old trick, not original to me). In the attached photo you can see the seal is concave due to the pressure exerted via the dough... and the dough plug came out in one piece.

[WmRMeyers]

Pretty clever. Thinking about this I'm recalling somewhere reading about how the paper towel makers have been changing the mix of materials to include fine filaments that add substantially to the wet strength of the towel. I think this is the key to it all. When sufficiently packed into the confined space the wet towel material essentially solidifies sealing the insides of the ball bearing and turning it into a piston of sorts. You can't do this with plain grease or any other true liquid material that will simply be forced past the bearing shields (or seals as the case might be) by the "hydraulic pressure" created by the hammer blows and the high pressure shock wave that they produce.
The bottom line here is that a combination of knowledge of basic physics and strength of materials is critically important to the skill development of all mechanical technicians and not just the engineering types (like me). Not that tribal knowledge isn't important. But an understanding of underlying science can save a lot of trial and error.

I'd not care to bet on that if I were you, Ed, as I've done it with grease and pin that fit the bearing tightly. I know just grease will do the job if the pin fits well. Remember this is in a blind hole. Unless the shields are just flat gone-rusted out or worn away, they'll still apply the force of the compressed grease. Will it work better with paper towel? Haven't tried that method myself, so couldn't say, but I know it can work with only grease. I've done it. Though honestly I hope I never need to do this again, either!

Bill

[Ronj]

Stiff, almost dry mud works very good also.

[JoeVanGeaux]

This is one of the coolest tricks I hope to never need to use.

The instant that bearing popped out I said to myself, "I'll be damned!", at the very same instant the narrator uttered the same.

Thanks for sharing!

[dbat74]

HEAT. Heat up the outside and it expands a bit, loosening up the tight fit.