Seat Bushes - solid or flexible?

Pentode

Dedicated Member
Supporter
British Zeds
Joined
Jul 6, 2023
Points
29
Location
Kettering Northants
Model of Z
Z3 Agean Blue Edition 2.0
Hi,

A bit of a ramle - sorry

I know changing seat bushes is covered a lot and sorry if it has particular question has been mentioned else where.

Just been undertaking this task of changing these on my car - driver’s seat done, passenger seat to follow.

Looking on the likes of e-Bay I could find plenty of people offering replacement bushes. I purchased some of a UK company, who also had a helpful video on how to do the job.

The bushes supplied are made from solid plastic (Delrin I think) and the video stated that you sand these down until the threaded block will just fit in to the carrier and press it in the rest of the way with a vice. This means the threaded block is help rigidly in the carrier between the platic bushes.

Put everything back together and tried to move the seat and ..... nothing! The motor wanted to move but the system was jammed.

Looking at the old bushes (what was left of them anyway) these are not a solid material like Delrin and look like they are made from a synthetic rubber - probably SBR. With this I would expect that the threaded block would not be held rigidly, but would have a degree of movement. I am sure the threaded rods while generally straight, may not be 100% true and some movement of the blocks would overcome this.

Based on this I stripped down the runners again, removed the bushes and sanded them further so the threaded block fitted snugly, but was free to move. Put everything back together and hey presto, the seat moved fine.

Taking a look on e-bay again it would seem that some of the bushes available are made of hard plastic, but others are made from material that has a bit of flexibility, such as thermoplastic polyurethane which will allow the threaded block to move.

What has other people’s experiences out there? Have you used rigid plastic bushes with no issues, or feel bushes made of a softer material are the way to go? From my experiences, I would say the latter!

Regards,

Nick
 

RB2

Zorg Legend
British Zeds
Joined
Sep 1, 2022
Points
76
Location
Inverurie, Aberdeenshire
Model of Z
Bogo
I just took 4 x 12mm washers and ground 4 flats on each. All back in without a wobble and fixed with bits from the shed. The seat moves freely.

A photo before I ground the tops flush.


20230829_142940.jpg
 
Last edited:

RB2

Zorg Legend
British Zeds
Joined
Sep 1, 2022
Points
76
Location
Inverurie, Aberdeenshire
Model of Z
Bogo
One thing I did notice was the center threaded bit isn't square. It is possible to mount it with the wider cross section vertically. If you do this is will catch the seats rivets
 

NZ00Z3

Zorg Guru (IV)
Supporter
New Zealand Zeds
Joined
Dec 9, 2014
Points
158
Location
Timaru, New Zealand
Model of Z
3.0L, 2.8L, 2.0L Z3 Roadsters
One rod is left hand thread and the other is right hand thread. Put them in the worn side and the seat does not move. Your problem was likely this and has nothing to do with the bushings
 

Nodzed

Zorg Expert (II)
Supporter
British Zeds
M Power
Joined
Feb 18, 2016
Points
231
Location
Forest of Dean, Gloucestershire, England
Model of Z
Z3M Imola and Z4 (e89)
The bushes should be sanded down so you can fit them by hand, there needs to be a very small amount of play so the thread block doesn't jam. Also the thread blocks must be refitted to the same point on the thread or the seat will not be square and will jam.
 
Top