Help needed, 1959 splitscreen castle nut

[BigRob]

Hi

I’m after some help, I was inspecting the rear brakes on my 1959 splitty, all was good and going well, untill I put the drum back on and began to tighten the castle nut. With very little force with an 18” wrench I managed to strip the thread on the nut. The hub appears to be ok.

The problem in having is finding a castle nut that fits. The 24mm inside diameter nuts from VW heritage are far to big, and all other I find appear to be to big as well. When I measure the hub thread it measure 19.5mm. Does anyone know what nut I’m supposed to use. The van haas the reduction boxes on it still.
I was also wondering if the thread on the hub may have been re cut at some point in its history making it smaller.

Any help/ advise would be much appreciated

Rob

[type21f]

Maybe lost in translation but I also thought axle nuts are two sizes
36mm and 46mm
Early bus is 36mm but across flats so as you say a m24 nut?

36mm head
M24x1.5
Looking at m24 nut sizes that looks like what should be the stub dims or am I wrong?

This nut size
https://www.customandcommercial.com/vw- ... sh66_2390/

If it is still on the original rgbs that is what I would have expected..

[BigRob]

Hi,
I was expecting it to be m24, with a 36mm outside diameter. The problem I’m having is that is seemes to be smaller than that.

[type21f]

Yes..the obsolete parts lists lists three the middle one is for m216..
Part numbers to check..
Is the other side the same size?
Yes two early ones at 36mm (without collar and with shallower collar? for 1500cc engine..)
So sounds like it has been turned/ tapped down?
May explain why it galled/ stripped.
Lot of work but early stub axles with 1.39 gearing are easier to find..
Rather than the taller THING items..
Or if replacing nut will need to establish size n pitch..

[BigRob]

Just been and checked. The other one is bigger and the new M24 36mm outside diameter nut fit just fine.

[type21f]

OK..
So decision work out what it has been reduced to and find a nut or strip n replace!
Sounds like an M20 castelatted nut?
What is the Across Flats size of the stripped nut as a start..
Is it Imperial or metric?
If a US bus could be US thread sizes..

Sure I have a stripped pair of early stub axles from vwjim.. but 100 miles away from me to look.

You will love the next question..If you choose to go down the change the stub axle you will need to know what you have..
Do you know if the rgbs are original 1.39 ratio or taller 1.26 ratio.
18/25 or 19/24 ratio?




From a 62 ish early ratio..count the teeth by removing the fill plug marking and rotating and counting the teeth.

[BigRob]

Just measured the stripped nut size and it is 20mm on the inside and 33.5 on the outside

[type21f]

Is that across flats?

[vwJim]

Sounds like the best option is fit a new stub shaft. Then it'll be back to the OG strength and won't have this problem in the future.

I think I've one set of small nut reduction boxes going spare.

[BigRob]

It was measured across the now flat inside edges of stripped nut.

If I can’t find another but it might be better to replace.

[BigRob]

Sounds like the best option is fit a new stub shaft. Then it'll be back to the OG strength and won't have this problem in the future.

I think I've one set of small nut reduction boxes going spare.

How much would you want for them?

[BigRob]

Sure I have a stripped pair of early stub axles from vwjim.. but 100 miles away from me to look.

You will love the next question..If you choose to go down the change the stub axle you will need to know what you have..
Do you know if the rgbs are original 1.39 ratio or taller 1.26 ratio.

Your right I have no idea of the size, if I cant find a nut, I will strip it and count the teeth. It might be best to go back to stock,

[type21f]

Do not need to strip..
If you remove the fill plug you can see the teeth!
Wipe with cotton bud, mark with paint on side n rotate..not easily done but possible..easy off the bus!

[BigRob]

Can I get to the fill plug buy taking the wheel off?

Sorry for the newbie question I’ve only had it for two weeks, and it’s by first one too.

[type21f]

We were all newbies once..! Location of plug.. in rgb housing.
Item 23.
Jack up support but need to be able to rotate the brake drum..