| 1. |
Due to limited access to the bolts on the seat rails once the seats are out of the car it's necessary to remove the seat nuts/bolts in a certain order. So, slide the seat all the way forward and with the 16mm socket remove the 2 bolts. Then with the 16mm spanner undo the seatbelt mounting bolt and move the seatbelt out of the way. (pic 1) |
 |
| 2. |
Next slide the seat all the way back and with the 13mm socket remove the 2 nuts. The seat should now be loose. (pic 2) |
|
| 3. |
Now it's time to undo the electrical wires underneath. This may vary depending on which Z3 you have but with my M Coupe there are 4 connections on the passenger seat and 3 on the drivers seat. I found it easiest to start with the larger connections which are around the middle of the seat. Here I lifted the seat up and pulled the whole thing forward, then tilted it back giving me reasonable access to the bottom. There are large connectors next to each other so unclip those. |
|
| 4. |
With the first 2 connectors released it should give the loom some slack, it may be clipped/taped to the seat frame in places and if so then unclip/cut the tape to free the loom. Now pull the seat level again and with it still as far forward as you can get it lift up the rear and you will see 2 connectors on the passenger seat and just the 1 connector on the drivers seat. They are at the very back of the seat and access it fairly easy. Unclip the connector(s) and the loom should now be free. |
|
| 5. |
Lifting the seat out of the car can be tricky (though I've had harder!) so here it's just a case of finding what works best for you. I found it pretty easy to just tip the seat out of the door from the top and then lift it out, being careful not to scuff any trim or indeed the seat. Once removed you will need something suitable to rest the seat on upside down as all the work now is on the bottom of the seat. (pic 3) |
|
| 6. |
With the seat turned over and resting securely on a bench or similar you can get a good look at the mechanism. However, you won't be able to see the rubber bushes we're going to replace as they are tucked up inside the runners. You will also see how the large T50 Torx bolt would have been covered if we hadn't moved the seat all the way back before disconnecting the wiring. |
|
| 7. |
Now with removing the seat runners I've seen it done where both are removed and replaced together. I just naturally did one side at a time and it meant I didn't have to worry too much about alignment of the runners afterwards as I'd left one attached while the other was off. It's entirely up to you whether you do one or both together, just remember to mark the positions carefully if you do both! (pic 5) |
|
| 8. |
So with the T50 torx bit remove the large bolt at the rear (top) of the runners. Then with the T20 torx bit remove the 2 smaller bolts half way along the runner. With those 3 bolts removed the seat runner will now slide up and down freely. (pic 4 & 5) |
|
| 9. |
To remove the mechanism you now need to slide the seat rail all the way back while at the same time holding the end of the rod and pulling/waggling it around a little. It's a tight fit but should eventually fall out and you now have what has often been referred to as "the kebab" in your hands. |
|
| 10. |
With the rod removed you can finally see where the offending rubber bush is and see what kind of condition yours are in. Mine weren't actually too bad though it still caused a rocking motion with the seat and I was able to rock the mount in my hand so it's clearly a bit of a design flaw. To get access to the rubber bush it's necessary to unwind the mount, so here it's important to make a note of how far down the rod the mount is positioned. I used some insulation tape and just wound it around the rod under where the mount was positioned, though as I was doing one side at a time I wasn't too bothered about how accurate the marking was. (pic 6) |
|
| 11. |
Unwind the mount and set the rod aside. With the mount in your hand you can nor remove the threaded metal centre and the rubber bush, there is a hole on the underside to help removing the parts if they are tight, but they will probably fall out as that's why we're doing this upgrade! It's worth noting that the standard rubber bush is a single piece with 2 folds, while the replacement bushes are 2 separate pieces, allowing the use of better material. (pic 7 & 8) |
|
| 12. |
The new nylon bushes have been made a little too thick to simply slot in. Whether this was by mistake or on purpose this means it will be necessary to sand the bushes down until they are a tight fit. So with some sand paper or emory paper place it on a flat surface and then start rubbing away. I removed about the same from a pair of bushes for each side, and simply checked regularly until they started to slide into the mount. There have been different things said about how tight they should be, and I've rad of one person having to take his seats in and out 4 times as the adjusting mechanism wouldn't work for some reason. I only did it once, fitted them pretty tight and it seems fine so here you will just have to use your own judgement, there is no right or wrong way, only YOUR way. (pic 9, 10 & 11) |
|
| 13. |
Now the new bushes are fitted to the mount simply wide it back onto the rod down to the marked position. The next step is probably the most fiddly of the entire job, fitting the rod back to the sliding mechanism and inserting the adjusting rod. The first time I did this it must have taken about 20 minutes or trial and error in trying to get it all back together, though I ended up with a fairly decent way of doing it in the end. So, with the sliding mechanism all the way back (to the same position when you removed the rod) insert the rod back into the mechanism and wiggle/push it down until it comes to a stop against the adjusting rod. |
|
| 14. |
The adjusting rod is a small rod with a square end that needs to be inserted back into the end of the rod we've just replaced. However, there is a fair amount of movement in the rod so it doesn't just slide into place, it has to be fiddled with! I used a small flat head screwdriver to push the little rod down a little whilst at the same time pushing the larger rod onto it. There is a little square hole in the sliding mechanism that if you put it in the right place will give you a little access window to the area your trying to work on. It does take a lot of trial and error and you may find a better or alternative way of getting the 2 rods back together, but eventually it will all slot into place and the mounting holes will line up. When they do, pat yourself on the back and re-fit the T50 bolt and the 2 T20 bolts, and that's one side done! (pic 12 & 13) |
|
| 15. |
Repeat steps 8 to 14 on the other seat rail. |
|
| 16. |
With that completed it's now simply a task of refitting the seat to the car in the reverse order of removal. Rear seat loom connectors first, then the larger middle ones. Then the 13mm nuts, move the seat forward to fit the 16mm bolts and the seatbelt mount. Here it's important to check the seat does still slide back and forward. It may be a little more labored than before but that's due to the additional tightness we've added to the mechanism. Also, if the seat does seem to sit on it's mounting points properly you may have messed up aligning the seat runners when re-fitting them. Sadly it's a case of pulling the seat back out of the car and removing the rods to adjust how far up or down you wound the mount onto the rod, so lets just hope that doesn't happen! |
|
| 17. |
Assuming you've done everything right you can now sit back and enjoy rock-free seats in your Z3 :) |
|
designed by: 
