Bearing removal - hydraulic trick

[scottm]

Some guys have seen this, others might not. When you can't get to the back of a bearing outer race to push it out, you can fill the bearing cavity with oil and tap a close-fit shaft into the center to lift it out. In this case I had two bearings in a housing on opposite sides of a step, and couldn't get to the outer races. I put a shaft in the lower bearing and hammered a Thompson shaft into the upper. The resulting pressure under the bearings lifted them just enough to get a screwdriver onto the outer races and tap them out. They need to be sealed or shielded bearings for this to work well, these seals blew out pretty quick from the pressure.

 

[PAToyota]

Wet paper towels or toilet paper works better by being more solid than oil - also less mess.

 

[scottm]

Quick sketch might clarify. The fluid is between the housing (red) and the bearing (green). When the shaft (magenta) is pushed down it creates pressure under the bearing forcing it up.

 

[PAToyota]

Yep. Wet toilet paper pulp works the same way, but less mess.

 

[scottm]

I'll have to try that. I thought about using just water, any incompressible fluid that will flow and not trap much air would work well. Grease when it's on it's side or upside-down. I'm usually in the shop with plenty of rags, making and cleaning messes all day. This was in a guys house, I used a big oil change pan and a towel underneath, but not much oil ended up spilled or splashed.

 

[rusty_tlc]

I used Multi Purpose Grease, the pilot bearing on the FJ60 popped right out.

I didn't have a steal dowel that was close so I turned one out of hardwood that was a close fit. It lives in the "Special Cruiser Tools" drawer of the tool box now.

 

[Mace]

A clutch centering tool works great for that pilot bearing as well

A input from a old three speed tranny works killer as well.
Only good use I can see for those old three speeds

 

[PAToyota]

As I was starting out in my automotive mechanic-ing, the grease trick was shown to me. Years later, I was shown that the toilet paper/paper towel method worked just as well with less mess to clean up afterwards.

I also think that it works better when there is some leakage through the bearing. As you found with the oil, lighter viscosity will find any hole it can go through as it builds pressure. The grease would do much better than the oil on that account. But the paper is much, much harder to squeeze through holes and works even with a "leaky" bearing.

 

[scottm]

I had to give up on these once the seals blew out, but they moved enough to access the outer races and push them out. Wet paper probably would have plugged all the holes between the bearings nicely. Next time. These ball bearings are being improperly used in a thrust application, made worse by my modification that adds more weight to the caster wheels, and missing covers that let in grit and moisture. I may have to replace them every year or two.

 

[Trollhole]

I use bread to get my bearing out. Has never failed me.

 

[PAToyota]

Had forgotten about that version - white bread without crusts seems to work best.

 

[Trollhole]

Bread also works well in repairing copper plumbing pipes. Stuff it in and it keeps the water from flowing during soldering and messing the joint up. Then just open a hose bib or take the strainer off a sink and it will shoot out.