Replacing the shock absorber (BMW 3 Series E21)

Removal

Remove the telescopic stand.

Clamp the stand in a vice.

Compress the suspension strut spring.

Remove the shock absorber piston rod self-locking nut cap and unscrew the nut while holding the piston rod with a wrench.

Screw the guide sleeve 31 3 115 onto the entire length of the threaded part of the shock absorber rod and relieve the compression buffer and the strut spring.

Remove the top support from the rack.

Remove the upper support cup with the plate, spring, compression stroke buffer and protective cover.

Using a 31 3 150 wrench, unscrew the strut housing nut and remove the shock absorber cylinder from the strut housing.

Installation

Drain the oil from the strut housing.

Pour 3 cm³ of fresh engine oil into the strut housing.

Insert the new shock absorber cylinder into the strut housing and tighten the strut housing nut.

Install the protective cover and compression buffer on the strut.

Install the strut spring and the upper support cup, making sure that the spring coils fit into the recesses of the support cups.

Compress the suspension strut spring.

Replace the upper strut support by installing the parts in the following order:

• large diameter washer;
• sealing washer, the convex side of which should face the upper support;
• upper support;
• small diameter washer.

Tighten the new shock absorber piston rod self-locking nut and cover it with the cap.