ausmini
https://www.ausmini.com/forums/

Diff difference
https://www.ausmini.com/forums/viewtopic.php?f=2&t=73306
Page 1 of 1

Author:  Irish Yobbo [ Thu Sep 29, 2011 3:52 pm ]
Post subject:  Diff difference

Hey all,

I'm rebuilding my gearbox, and I have a second gearbox for parts (since this box was recently rebuilt but has had the box damaged).

Looking at the two diffs, the bearings are quite different. The old one seems to have a plastic cage that has collapsed. The newer bearings seem to have a metal band as part of the cage, and they are still thrust bearings.

Image
The upper one has been rebuilt (I believe - the rest of the gearbox had been). The lower one hasn't seen the light of day since 1978.

Image
The old diff close up with it's cage falling out.

So the question: do I treat the new bearings the same as the old type i.e. preloading shims and the like? Are these bearings the right ones for the job?

Edit: I suppose you might want some numbers:
The old bearings have the number 2LJT34.9
The new bearings have 17LJT13/8

Author:  drmini in aust [ Thu Sep 29, 2011 4:06 pm ]
Post subject: 

Original diff bearings were a deep groove ball bearing, both sides looked the same and you could fit them either way round. Preload on these was only .001".

Later type are angular contact bearings, and are marked `thrust' on the outer ring. These only can fit 1 way and are preloaded .005".

I have been told this 2nd type is NLA now, most places are selling the early type again- which are a standard size ball bearing.

Author:  blue_deluxe [ Thu Sep 29, 2011 5:02 pm ]
Post subject: 

Chuck a 4 pin in there while youve got it all apart.

Author:  Irish Yobbo [ Thu Sep 29, 2011 6:47 pm ]
Post subject: 

blue_deluxe wrote:
Chuck a 4 pin in there while youve got it all apart.


This must be to handle the monstrous torque delivered by my unmodified 998 :)

Now, another question related to the gearbox: The threaded rod that attaches to the actual box and holds the levers that controls the selector forks spins when I try to turn the nut. This is the threaded rod that is attached to the circle at the bottom of the box. When I dismantled the last box, the nut came straight off, but with this one, it's turning the whole lot. Any suggestions on how to get the nut off, and will this cause the box to leak in the future?

Author:  blue_deluxe [ Thu Sep 29, 2011 7:01 pm ]
Post subject: 

Irish Yobbo wrote:
blue_deluxe wrote:
Chuck a 4 pin in there while youve got it all apart.


This must be to handle the monstrous torque delivered by my unmodified 998 :)


Depends how long you want it to last

Author:  mattsmadmini [ Thu Sep 29, 2011 7:34 pm ]
Post subject: 

blue_deluxe wrote:
Irish Yobbo wrote:
blue_deluxe wrote:
Chuck a 4 pin in there while youve got it all apart.


This must be to handle the monstrous torque delivered by my unmodified 998 :)


Depends how long you want it to last


A single competition pin from Karcraft would be more than sufficient for and unmodified 998.

Author:  Morris 1100 [ Thu Sep 29, 2011 7:41 pm ]
Post subject: 

mattsmadmini wrote:
blue_deluxe wrote:
Irish Yobbo wrote:
blue_deluxe wrote:
Chuck a 4 pin in there while youve got it all apart.


This must be to handle the monstrous torque delivered by my unmodified 998 :)


Depends how long you want it to last


A single competition pin from Karcraft would be more than sufficient for and unmodified 998.

I was thinking that a broom handle...

Author:  peterb [ Thu Sep 29, 2011 11:52 pm ]
Post subject: 

Foget the pin, fit a CIG limited slip :o)

Author:  sitnlo62 [ Fri Sep 30, 2011 8:02 am ]
Post subject: 

To answer your question,
Yes Both these Bearings you have pictured can be treated as the same.

They are both THRUST type bearings.

The thinner bearings in the lower part of the photo are in fact the newer of the two...

The bearings in the upper photo are the first of the THRUST type, not to be confused with the very early deep groove ball bearings used in early cars.

Hope this helps,
Dave

Image

Page 1 of 1 All times are UTC + 10 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/