'92 129 500SL seat information

[mikec1231]

Does anyone know if the seats from a '92 Mercedes 129 500SL will work in a 2-door car with a back seat? They need to fold forward to get into the back seat. Also need to know the width at the widest point on the seat if anyone is driving one.
Thanks
Mike

[jjrodger]

What kind of car do you want to put the seats in? Reading between the lines, not another R129! In which case, my instinct says No.

The seats in the R129 are quite unusual. They form part of the roll over protection for the occupants of the car. They have a substantial and bulky magnesium frame. It would surprise me if the seats fit into the car in a standard manner.

The seatbelt is part of the seat frame. All of the cars have a very complex electric seat adjustment system which automatically adjusts the angle of the backrest and the height of the seatbelt depending upon the position of the squab.

[mikec1231]

I am putting the seats into a '39 Chevy 2 door sedan street rod. I liked the idea of the integrated seat belts into the seats as well as the power seat unit. I need to be able to flip the seat forward to enable passengers to access the rear seat. Frabricating new mounts for the seats is no problem as I am able to weld, etc. Mounting shoulder harness seat belts is a bit difficult on a 2 door car from this era.

[jjrodger]

I have looked into this at Alldata.com and also thought a bit more about it. The seats are really complex. There are all kinds of sensors (eg back rest position sensor). Here follows the instructions and a diagram. You will see the seats are not mounted to the floor but rather the transmission tunnel and door sill. This procedure gives you the seats, but not the electric adjustment of them, which looks phenomenally complicated. The seats are very comfortable!

Front seat (1)
move all the way to the front with forward/backward adjustment mechanism.

Screws (2, 3, 4, 7 and 8) (5 each)
unscrew on rear of seat rail at left and right 17 Nm.

Screw (9) (1 each)
unscrew at front on right seat rail 17 Nm.

Front seat (1)
allow to run toward rear with forward/backward adjustment mechanism.

Screws (5 and 6) (2 each)
unscrew at center and front of left seat rail. 17 Nm.

Ignition key
turn to zero position.

Negative pole on battery
disconnect and cover.

Red 10-pin connector in footwell
disconnect.

Connectors on control module (12)
disconnect, open cable straps and expose cable.

Front seat (1)
when removing first tilt toward outside and then lift out of vehicle together with a second person.

Reinstall
in opposite order.Observe installation note.

Installation note
The threads on the seat mounting screws (8 each) are micro-encapsulated. Following disassembly they must be replaced or coated with screw securing agent.
Tightening torque:17 Nm.

Observe the following sequence when tightening seat mounting bolts:


All bolts on outer seat rail on longitudinal member.
Both rear bolts on inner seat rail on tunnel floor.
Front bolt on inner seat rail on tunnel floor. Compensate gap resulting here between seat rail retaining bracket and tunnel floor console with washer, part no.129 984 00 56
Vehicles with airbag
When one or both front seats are removed (connectors to seat belt buckles must be disconnected) the SRS malfunction indicator lamp comes on when the ignition key is in position 1 or 2 and goes out when the seats are reinstalled after reconnecting the disconnected connectors.
This is stored as a malfunction in the control module for the airbag and emergency tensioning retractors. The memory must be erased after reinstalling the seats. See: Restraint Systems

[G-Benz]

Cool diagram jjrodger!

I've had mine apart to replace a broken shaft on one of the motors (had to replace the whole assembly...$350!!!).

Except for the the SRS sensors, the big module mounted under the seat cushion harnesses the power supply for the entire seat operation mechanism. There is a big harness bundle for each seat operation that plugs into the module.

I never actually replaced the broken shaft yet, but its operation would cause the seat to lean towards the passenger side...so I unplugged the harness that facilitates its operation...pending replacement of the offending motor...