Seat Problems - up/down + seat back stuck

[maxz3]

Hi,

New to this, wondering if someone can please help.

Recently bought a 97 Z3 1.9 with some minor issues with the seats.

The electric motor does go backwards and forwards but the up/down just makes a noise with no movement.

Also, the back of the seat is manual, but when I pull on the handle, the seat stays bold upright with no movement. I have oiled, but no joy!

These problems identical on both seats!!

Has anyone got an idea as to what it could be?

Also, on the 1.9 engine, are they belt or chain driven?

Thanks in advance.

Max

 

[zedonist]

Hi Max, first welcome.......

Second the M44 engine is chain driven so no need to worry about cam belt changes, and as long as it is serviced well and regular should be bomb proof (use good oil - Fuchs Titan Supersyn for example).

The seats each have two motors, one for the front / back motion and one for the up / down motion, if you can hear the motors but have no movement, then something may have become loose / broken or trapped in the mechanism, I would suggest taking the seats out and bench testing, you will see what is not working that way, hard to diagnose otherwise.

The manual adjustment on the backrest is spring loaded, if you pull on the lever and have no weight on the backrest it will spring up to top position, to lower the back, just pull on the lever and lean into the seat.

Hope this all hopes, keep us posted on the seat motor issue

 

[GazHyde]

Welcome @maxz3,

I've heard of both problems, but not both seats in the same car at the same time. The good news is that they go back/forwards as that will at least allow you to get to the back bolts to remove the seats if needed.

As usual Zedonist has hit the nail on the head with the course of action. If you need any motors, let me know as I have a couple spare somewhere.

Cheers, Gary

PS I've added you to the "M44 Massive", an exclusive club for 1.9 owners

 

[maxz3]

Hi Guys,

Thanks for getting back to me!! I will get the seats out and try and assess whats going on! Will keep you updated!

 

[metalmickey]

Hi Max
There are at least a couple of good posts on removing the seats and replacing the bushes on the threaded spindle/cage that the motors turn to adjust the seat position.
You may have 'rocking seats' which is movement apparent under breaking and cornering. The solution is to replace the original rubber bushes with new polythene ones available from aceman on this site.
If you are taking your seats out to investigate this motor problem it would be a good time to do it.
Good luck.
MM

 

[hard top]

HTH,,,,

http://bmwfans.info/parts-catalog/Z....9-M44/R-N/1997/browse/seats/front_seat_rail/

 

[Aceman]

Hi Max
There are at least a couple of good posts on removing the seats and replacing the bushes on the threaded spindle/cage that the motors turn to adjust the seat position.
You may have 'rocking seats' which is movement apparent under breaking and cornering. The solution is to replace the original rubber bushes with new polythene ones available from aceman on this site.
If you are taking your seats out to investigate this motor problem it would be a good time to do it.
Good luck.
MM

Thanks for the plug as said if you need any bushes just give me a shout or click the link in my sig.

 

[jonco]

Note: Once you have the seat unbolted you need to disconnect battery earth before removing as there is a risk of firing belt pre-tensioners. IIRC you will then have to reset airbag light once re-installed.

 

[metalmickey]

I did mine without disconnecting the battery but I was careful not to leave the key in the ignition as advised. I reconnected the electrics and all worked perfectly as before.
MM

 

[Lee]

I did both sets of seats in both my zeds a few weeks back. One seat suffered with a dead motor.

Very simple to strip down prize open the prongs at both ends then the central shaft slides out with little magnetic pull.

Once out i noticed the commutator was covered in carbon (copper finish covered in black deposits). Once i clean it and reassemble the motor i did a continuity check spinning the motor by hand. It should give you a reading while rotating. You can even test the motor by using a 12v car battery (aka my dad’s caravan battery)

Things worth noting: inside the top cap there is a small capacitor that looked like a weak point. one of my engineers pointed out it was an off the shelf item from maplin if its failed (proven by a continuity check)

Another thing i encountered was when assembling the motor shaft through the centre top cap you will struggle to push the brushes back and get the shaft in (Due to size of fingers and small gap) i curled a piece of paper to hold the brushes back.

I went through this process with all my motors as a preventative measure. If this proves useful i could always make a pictured write up in detail.

Lee

 

[oldcarman]

Hi Lee, from someone that needs all the help he can a pictorial would be a definite benefit to me and probably other. JIM

 

[Steve F]

On the vertical seat control. If it sounds like the motor want to run but hums, most likely the gear drive is bound up. You can sometimes free it by forcefully shaking the seat up and down while activating the actuator. If that doesn't work you'll have to pull the seat to free it by spinning the drive cable.

The tilt control is by cable connected to two ratchet mechanisms inside the seat back and base. If the cable has come loose, it can be reconnected with needle nose pliers while the seat is out. If one of the ratchet mechanisms has failed, the entire seat must be disassembled to replace it.

Hi Lee, from someone that needs all the help he can a pictorial would be a definite benefit to me and probably other. JIM

What pictures do you need? I have many of the seat control system available.

 

[oldcarman]

Will need to wait till my car get to Canada sometime in around May 19. The seller informed me that there were a few small problems but hasn't specified. Thanks for the offer, will keep in touch or PM me whatever you think I could use for a 97 m44. JIM

 

[jonco]

Will need to wait till my car get to Canada sometime in around May 19. The seller informed me that there were a few small problems but hasn't specified. Thanks for the offer, will keep in touch or PM me whatever you think I could use for a 97 m44. JIM

Jim,
Between us we will have loads of photos applicable to the M44 - just shout when you need them
Colin

 

[GazHyde]

What pictures do you need? I have many of the seat control system available.

We are always looking for people to write articles for the benefit of other members... A general article on how the seat bases, motors etc are positioned and work together would be very useful

 

[bonbon]

For years my up/down has been seized on the driver's seat. Seems it's a mechanical problem as I can hear the motor humming but there is no movement.
A few years ago I had the seat out and jiggled with the motor (raised the seat manually) - when reinstalled it worked for 5 seconds and jammed again.....any insights would be appreciated as I plan to remove the seat shortly.

 

[Steve F]

For years my up/down has been seized on the driver's seat. Seems it's a mechanical problem as I can hear the motor humming but there is no movement.
A few years ago I had the seat out and jiggled with the motor (raised the seat manually) - when reinstalled it worked for 5 seconds and jammed again.....any insights would be appreciated as I plan to remove the seat shortly.

There are a few things that could cause these symptoms to repeat, weak actuator motor, sticking transmission or worn or dry hinge points. Depending on year, there is also an inline circuit breaker that could cause problems. As stated above, cleaning the motor contacts could solve the problem, but I've never done that.

I have a huge collection of seat parts. Depending on where you are located and shipping costs, I may be able to help you out if you determine what you need.

 

[zedonist]

Good offer of help, love this forum!

 

[bonbon]

Thanks Steve,
Will it be easy to identify the problem once the seat is out?
Or should I just tilt the seat up (once the bolts to the floor are removed) and try to see where it gets stuck?

 

[jonco]

...........Or should I just tilt the seat up (once the bolts to the floor are removed) and try to see where it gets stuck?

You really need the seat out on the bench to test -it's too much of a balancing act when it is in the car and you can easily scratch things ( does that sound like the voice of experience - it should do!!!)