MTFCA Forum

I have some used axle shafts I plan to use with good threads and key ways. The specs I've found for the bearing surface is 1.060-1.062 when new. I'm measuring something less than that, but more than 1.051 across the length. Is there a replacement threshold? The ones in the car now would probably measure 1.000 or less. They've likely been that way for a long, long time.

The spec is 1.0625. I am particular in all my builds. 1.059 - 1.060 is my minimum with mint bearings & new sleeves. There should be no up & down movement after assembly, but the bearings should slide in without a hammer. Undersized axles should polish smooth. No pitting or surface break down.
Do not except a used axle with a wear groove from an inner leather seal spring tensioner.

I'm measuring something less than that, but more than 1.051

Not too much to go by there. It seems as if they may be worn too small to use with Hyatts. I would save them for use with a floating hub set-up and go with better, or new, axles.

Worn axles will ruin good Hyatts. Worn Hyatts will ruin good axles. Worn sleeves will ruin everything. It all needs to be in excellent condition to last a long time.

Jerry VanOoteghem wrote: ↑

Mon Mar 24, 2025 3:16 pm

I'm measuring something less than that, but more than 1.051

Not too much to go by there. It seems as if they may be worn too small to use with Hyatts. I would save them for use with a floating hub set-up and go with better, or new, axles.

Worn axles will ruin good Hyatts. Worn Hyatts will ruin good axles. Worn sleeves will ruin everything. It all needs to be in excellent condition to last a long time.

Well said.
Cutting corners with any one component will damage the others & shorten its operating life.

Always a good idea to magnaflux used axels when building a rear end. In addition to size, the bearing surfaces should have no visible flaws and the threads and keyways should be in great shape- if not, you have good tent stakes!

Pretty much going through the same thing with my rear axle. Whoever went through it prior to my ownership, cut a few corners and it ruined just about everything inside it. The housings and torque tube are about the only thing being reused; the rest will be wall art for the garage.

Jerry VanOoteghem wrote: ↑

Mon Mar 24, 2025 3:16 pm

I'm measuring something less than that, but more than 1.051

Not too much to go by there.

I just meant that along the length of the bearing surfaces the measurement varied by a few thousandths from 1.051 to 1.060. Both axles have wear and seemed to taper from what I assume was the original unworn. Neither exceeded 1.062.

Apis Mellifera wrote: ↑

Mon Mar 24, 2025 9:41 pm

Jerry VanOoteghem wrote: ↑

Mon Mar 24, 2025 3:16 pm

I'm measuring something less than that, but more than 1.051

Not too much to go by there.

I just meant that along the length of the bearing surfaces the measurement varied by a few thousandths from 1.051 to 1.060. Both axles have wear and seemed to taper from what I assume was the original unworn. Neither exceeded 1.062.

Thanks for clarfiying. The .010" taper is too excessive, in my opinion. As I mentioned, I would keep then for use with floating hubs, if you ever go that route.

I disassembled the axle today and inside were the two large springs. They were between the inner and outer bearing and the axle shafts passed through them. I do not see these springs on any diagrams and don't recall reading about them. I also can't find a reference to them online. Anyone have insight?

Thanks!

They are an accessory item designed to wind IN the extra grease to keep the outer grease leaks down. Note they are wound in opposite directions.
IMO, they are unnecessary when using the modern neoprene inner grease seals. They could be of benefit if the seal surface on the axle is buggered up to not work with a modern seal.

I believe they are woodworth springs and do what John said. I had a set on my '24 roadster for a time but took them out when swapping an axle. Didn't really see a need to use them. Besides, if you accidentally put them in backwards ya gotta big mess, so I was told.

Agree with Speedy and Wing on the springs. I used them 40 or so years ago and will say I did not have leaking from the axle ends. Was this because of the springs? This was before the modern seals. I also agree that using the modern neoprene inner grease seals takes care of the problem.

Wingnut hit the nail on the head
I have some for sale https://mtfca.com/phpBB3/viewtopic.php? ... th#p298555