Removing Shinn Wheel Bearing races (cups)

[VASWIFT]

I have a set of Shinn wheels and I am trying to replace the bearing races (cups). Getting the small bearing race (# A6162) out is no problem since you can tap it out from the back. However, getting the large bearing race (# 08231) out is proving difficult since there is no way to tap it out from the back. The race has been "stacked" at three points and perhaps has Loctite to hold it in. I have tried to get it out using heat and slamming it on a board. Not budging. Using heat, I have tried to carefully pry it out by getting behind it and prying. No help.

There is little "lip" showing on the race to get a tool in there to use something like a "gear puller". Any ideas? I have searched the forum for help but have not found any discussions about this.

[M Towsley]

Re: Removing Shinn Wheel Bearing races (cups)

I'm trying to remember, but I think I used a good sized screwdriver with the tip bent over and go in from the other side. It has been awhile since I have done this but I am sure others will chime in. I think it is somewhere here on the forum.

[woodmw]

Re: Removing Shinn Wheel Bearing races (cups)

A number of years ago, I picked up a couple of paint can openers when I purchased some paint. These openers were shape like the screwdriver Marty described above. I think it was from Lowes/Home Depot, but may have been from auto paint store.

[VASWIFT]

Re: Removing Shinn Wheel Bearing races (cups)

Yes, good idea. I know the tool you are talking about. Will try it.

[Mark Julicher]

Re: Removing Shinn Wheel Bearing races (cups)

There was not much lip showing, but it was enough for me to tap my races out using a 3/32 pin punch.

[VASWIFT]

Re: Removing Shinn Wheel Bearing races (cups)

I used several of the "paint can opener" tools with no success. I can see that some "adhesive" (Loctite?) was used on the races that I could get out. Perhaps a "slide hammer" with "fingers" that go under the race might work, using heat to help. I might have to fabricate a tool to do this as there is no way to get anything behind the race to get it out. If only Shinn had put several holes in the wheels to get a punch behind the races. Fortunately, these are spare wheels so I can take my time in figuring this out.

If anyone has any ideas how to get the large races out of the wheels, let me know.

[Pearson]

Re: Removing Shinn Wheel Bearing races (cups)

If you can take the tire off and put it in an oven to heat it, the hole the race is in would enlarge with heat. I would not use a torch due to fire concerns with magnesium.

[Robert Lees]

Re: Removing Shinn Wheel Bearing races (cups)

I regret not videoing a similar thing many moons ago, where we were trying to get a bronze/brass bush out of a magnesium casting (nothing to do with aviation, and before cheap video camera were around).

We had that magnesium casting almost red hot with oxy-acetylene to get the bush out, and it did come out.

There was no threat of the magnesium catching fire...the surface-to-oxygen ratio has to be so high to get it to burn; a solid casting is very unlikely so to do. You normally need very fine shavings or particles.

[Hank Jarrett]

Re: Removing Shinn Wheel Bearing races (cups)

Heating and cooling will break the adhesive bond. It does NOT have to be that much, like ice water and "just too hot for your hand", going back and forth. The difference in rate of expansion will eventually fracture the "glue". Next is to push the race out with LOTS of light taps, NOT a few hard ones. If you can get an ultrasonic probe on the race it will move easier, lacking that a LIGHT setting on a rivet gun.
Hank

[astjp2]

Re: Removing Shinn Wheel Bearing races (cups)

If its the green loctite, you need 250+ to break the bond. I think its loctite 609 or something like that. Also the mag expands larger than the steel race and you get seperation there also. Tim

[Mark Julicher]

Re: Removing Shinn Wheel Bearing races (cups)

I remove my races using a long drift and tapping around the edge of the lip firmly from the inside of the wheel. Gear pullers seem to have fingers that are way too fat to work well. You may want to carefully file out the staked spots first. I found that there is enough of an edge showing that a drift with a square edge will do the job.

My Shinn wheels are aluminum not magnesium. PB Blaster or mouse milk might help loosen the Loctite - but I'm not sure about that.

[Hank Jarrett]

Re: Removing Shinn Wheel Bearing races (cups)

If the Loctite is Cyano based, Acetone will chemically break it down, but only where you can reach the surface. It could take a LOOOOONG time to dissolve it running down the space between the wheel and race.
An ultrasonic bath will speed that up.

Hank

[Ron Coleman]

Re: Removing Shinn Wheel Bearing races (cups)

OK! Here is how you do it. Clean the wheel to get all of the oil and grease off. You don't want it to cook into a glue. Prepare a clean work area with some soft pads to support a hot wheel. you should have a support with a hole in it large enough that the race can fall through when you place the wheel on the block over the hole. The block can be wood or metal like a disc brake plate, however if you use a metal plate it must be heated to about the same temperature as the wheel. A cold plate will suck the heat out of the wheel in seconds. Now place the wheel in a double boiler (no water) and cover the double boiler with a towel or the like to keep the heat in and turn the heat up to about 325 f. and let it heat soak (after it reaches 325 f. or about 20 min. Now quick like a bunny, using gloves of course, lift the wheel out, place it on the block and using a drift (flat end punch) tap around the race on the very edge in a triangular pattern and the race should come out if it has not already fallen out. If you get the race kattywampus it will stick and you will have to reheat it and start over. The wheel will loose it's heat in as little as a minute and will shrink enough to grab the race again, so work fast. Do not try to drive the race out if you get it out part way and it sticks. Reheat it and do it right.
This is also the proper way to replace the race. Put the race in the freezer (overnight is best) and see if it will drop in the wheel, if not freeze it again and heat the wheel and then drop the race in place.
If you press the races into the wheel with out heating you will eventually ruin the wheel and have to resort to glue, sleeves or new wheel.
This is important! When you place the wheel in the double boiler place it on a support so that the race can fallout clear of the wheel.

This is how I sleeve motorcycle cylinders and replace bushings in gears, etc. Also a helper makes it easier.

Have at it
RonC

[Ron Coleman]

Re: Removing Shinn Wheel Bearing races (cups)

One added note, it is important to heat soak the wheel. It usually takes 25 minutes or more after the temperature reaches 325 f. The metal will take that long to grow enough to break away from the race.

kRonC

[VASWIFT]

Re: Removing Shinn Wheel Bearing races (cups)

Hey, Ron, appreciate the info. Here is the problem - if you are familiar with the Shinn wheel half holding the large bearing race, there is no way to get behind the race to tap it out. It must be "pulled out", as there is no way to "push" (tap) it out. If Shinn would have put tiny access holes in the wheel portion which blocks access to the back of the race, it would be possible to use a punch to tap it out from the back.

The wheel half with the small bearing can be tapped out from behind.