Seal Hunting

[ByTheLake]

Funny how these little restoration projects can go from hot to cold in an instant. I suppose that's part of the fun.

As part of my CA95 restoration I'm replacing the seals in the front and rear wheel hubs. I found replacement rear seals in an instant. The seals (30x47x8 and 22x35x8) were common sizes, available from many sources. I placed my order, received my parts, and they matched the old parts perfectly. In awe at my apparent restoration prowess, I turned my attention to the front seals. I now knew the routine ... get the inside/outside/thickness measurements, find the generic seal, then grab them for a few bucks.

The front seals, however, put my ego back in check. These beauties (50x64x8 and 34x48x6.5) seem to be anything but common, and that last one doesn't even match the specs in the parts manual. Hmm.

For the 50x64x8 seal, a few NOS items are available for around $15, plus shipping, which seems high for an old seal. I'll probably order one anyway.

The 34x48x6.5 seal, however, is nowhere to be found. Perhaps this was previously replaced, and is supposed to be 7 or 8 mm thick, not 6.5? I'll study the hub to determine if I can squeeze in a 34x48x7 or go with a 34x48x6.

Anybody replace their front wheel seals?

[Sam Green]

Originally Posted by ByTheLake

Funny how these little restoration projects can go from hot to cold in an instant. I suppose that's part of the fun.

As part of my CA95 restoration I'm replacing the seals in the front and rear wheel hubs. I found replacement rear seals in an instant. The seals (30x47x8 and 22x35x8) were common sizes, available from many sources. I placed my order, received my parts, and they matched the old parts perfectly. In awe at my apparent restoration prowess, I turned my attention to the front seals. I now knew the routine ... get the inside/outside/thickness measurements, find the generic seal, then grab them for a few bucks.

The front seals, however, put my ego back in check. These beauties (50x64x8 and 34x48x6.5) seem to be anything but common, and that last one doesn't even match the specs in the parts manual. Hmm.

For the 50x64x8 seal, a few NOS items are available for around $15, plus shipping, which seems high for an old seal. I'll probably order one anyway.

The 34x48x6.5 seal, however, is nowhere to be found. Perhaps this was previously replaced, and is supposed to be 7 or 8 mm thick, not 6.5? I'll study the hub to determine if I can squeeze in a 34x48x7 or go with a 34x48x6.

Anybody replace their front wheel seals?

BTL, it's a thing I had never even thought of. If all else fails can you not replace the bearings with sealed ones, just a thought, might not look quite correct but it would keep you on the road.

Sam.

[ByTheLake]

Originally Posted by Sam Green

BTL, it's a thing I had never even thought of. If all else fails can you not replace the bearings with sealed ones, just a thought, might not look quite correct but it would keep you on the road.

Sam.

My front bearings are already the sealed type. Perhaps that means that somebody has already been here? They are in good shape, I'm retaining those. The items I'm referring to are the circular grease seals:



The larger one is available as NOS on eBay, for roughly 4x what a generic would cost, not considering shipping. The smaller one snaps into the speedometer drive housing and is just not available in the 6.5 mm thickness. I could go with a 6 mm however.

After inspecting these using my magnifying jeweler's visor, I just may retain the original ones. The sealing surfaces are in decent shape, unlike what I encountered with the rear hub. It's just that I like to replace seals when I have things this much apart.

[dickevins]

How do you get the rear bearings and seals out without harming them? (Now that I've got my rear tire, etc. removed.)

[Spokes]

Buy a 3/8" concrete anchor. Place the expandable part of the anchor into either side bearing and tighten the anchor nut until the expandable end of the anchor expands tight in the race.

From the other side, using a drift pin, metal rod or large screwdriver against the anchor base, drive the bearing out with a hammer.

Once one bearing and the spacer is out, using a close to bore size socket and extension, drive the other side out.

No need to remove the seals first as they will drive out with the bearings.

[dickevins]

Spokes:
What does a 3/8" Concrete Anchor look like? How does one avoid scoring the inner race of the bearing if a metallic object is jammed into it and then driven out with force?

[Spokes]

The anchor looks like this:


The anchor is soft steel. The bearing race is hardened. The bearing fit in the hub is indeed pressed in but drives out rather easily.

I know of no other way to remove the rear wheel bearing. I have removed several sets of rear wheel bearings this way..

Maybe another member has a different way?

[dickevins]

Thanks Spokes. I'll give it a try.