Steering box seals replacement

[325ix86]

Hello,

Just a short article I've written on the replacement of the seals on a steering box. It's valid for both 02 and 4 door New Class.

The original is in french, but google translate seems comprenhensive enough.

https://translate.google.com/translate?sl=fr&tl=en&u=http://www.6enligne.net/forum/index.php?/topic/169132-refaire-l%C3%A9tanch%C3%A9it%C3%A9-du-boitier-de-direction-dune-nk/

Enjoy

 

Edited March 29, 2021 by 325ix86

[325ix86]

Following 6enligne.net forum migration, it seems the link doesn't work anymore, I copy the text hereafter:

 

Procedure valid for 02 and Neue klasse sedan and coupé.

 

Release the ball joint from the steering arm with a puller such as Facom U.16B

 

Loosen nut A.

Remove screw B

 

Slide (Easier said than done) the flexible flange upwards and release it from the input shaft of the steering box
Unscrew screws 1, 2 and 3

 

Remove the steering box
I used the Wallothnesch rebuild kit  A 32 11 2 670 440 composed of:

•  32 11 2 670 107: Paper seal
•  32 11 2 670 114: Lip seal 18-30-7
•  32 11 2 670 110: Lip seal 28-42,5-8
•  07 11 9 935 670: Brake plate
•  07 11 9 921 659: Nut M22x1.5

 

A little cleaning

 

Remove the plastic plug at the top of the box and drain it

 

The origin of the legend of lifelong oil in the original owner book?
In any case after 52 years it is...

 

The midpoint of the steering box is identified by a line on the output shaft and a punch on the lever which line up with the rib of the box ...

 

And a line (light) on the input shaft which must line up with the triangular mark at the top of the case

 

Unfold the nut retainer

 

Unscrew the nut with a socket of 32
Tear off the steering arm with a Facom U.52 type puller

 

Unscrew screws 1, 2, 3 and 4. (When reassembling, seal the threads of screws 3 and 4 with Atmosit)

 

Remove the cover with the shaft end

 

Unscrew screws 1 & 2 with a 13 mm spanner and 3 & 4 with a 6mm allen key (On reassembly, seal the threads of screws 3 and 4 with Atmosit, and be careful with the direction of the plate; the machined edge downwards)

 

Press the shaft out of the housing

 

Note the order of the parts for reassembly and the number of shims so as not to disturb the friction of the input shaft.

 

Remove and replace the input shaft lip seal. I used a spark plug socket to chase it from the inside

 

Remove and replace the output shaft lip seal. I haven't found a better way than to blow it up to get it out.

 

Reassemble the input shaft with its 2 ball cages and the raceway without pushing it too far.
Reassemble the shim (s) and the cover (in the right direction). Gradually tighten screws 1 to 4 (Not having atmosit, I used Loctite MR 5923), while constantly turning the input shaft with a 10 mm open-end wrench, to push the raceway into position.

 

Reassemble the output shaft with its cover and the new paper seal.

Take care that the marks are perfectly aligned on the input AND output shaft. Tighten the 4 screws of the top cover.
Reassemble the steering arm with the punch aligned with the mark on the shaft.
Position the brake plate and fold it back along the arm. Tighten the nut to 120Nm. Then bend the brake plate against a flat of the nut.

 

Fill the box with 30cl of SAE 90, API GL4 oil.

 

Adjust the friction between 10 and 18 cmkp (Centimeter kiloponds) ?
What the hell is this? ?
Just a German unit which has not been used since the 1970s.
Well, after a lot of research, it must correspond to a friction roughly between 0.98 and 1.76 Nm.
Loosen the nut with a 19 mm wrench, and adjust the friction by turning the cover screw with a large flat screwdriver.
By using a short open wrench of 10, I have a lever arm of 8cm so with a force of 1.25 to 2.25kg applied at the end of the wrench that must be it. The friction value must be measured when passing the midpoint (Mark on the input shaft).
Be careful; check that the arm is in the middle point (Markings on the output shaft). By adjusting the screw in another position, there is a risk of having a much too tight play and damaging the case.
Once the correct friction value is obtained, lock the position of the screw by tightening the nut.

 

Reassemble the box on the cradle, check that it is properly seated in the positioning sleeves before tightening the screws.
Reattach the flexible flange by applying a preload of about 6mm while pushing the drving wheel. (Do not forget the horn cable)
Reattach the steering rod ball joint.

Edited May 6, 2021 by 325ix86
Pictures links correction

[NickVyse]

Great write up Fred! This should be an FAQ technical article - post it here:

 

https://www.bmw2002faq.com/articles/technical-articles/suspension-and-steering/

[steve k.]

Can you please attach all the images in the article instead of linking to them from.another forum. We do not want to loose them as has happened in the past. I'll turn it into an article in the FAQ once done.

 

Thank you,

Steve K.