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Garage => Interiors & Exteriors => Topic started by: raueda1 on 17 April 2022, 01:14 PM

Title: Another driver's seat repair thread
Post by: raueda1 on 17 April 2022, 01:14 PM
This season I'm gearing up to fix the well know sagging seat issue.  In many ways the seat sag places a real limit on car handling since I'm hanging onto the steering wheel when cornering. There hasn't been much on this topic recently so I figured I'd poll you folks for updated info.  Here are a few questions based on some preliminary searching:


I've had the seats in and out, no problems there.  I'd be reusing the existing seat covers (MB-Tex, heresy and damnation!!!).  Might upgrade the covers in the future, but not ready to do that yet.  Any comments, suggestions, experiences or recommended suppliers would be great. Thanks and cheers!
Title: Re: Another driver's seat repair thread
Post by: Alec300SD on 17 April 2022, 01:50 PM
Grab the PS spring boxes from 2 separate 2nd generation W126's at the local JY, change the seat skins over to your MB-tex covers, and install them place of your original spring boxes.

They offer superior support and are backwards compatible to the W123 and W116 seats.

http://www.peachparts.com/shopforum/diesel-discussion/352422-diy-%96-pictorial-w126-front-seat-cushions-w116.html
Title: Re: Another driver's seat repair thread
Post by: raueda1 on 17 April 2022, 02:35 PM
Quote from: Alec300SD on 17 April 2022, 01:50 PMGrab the PS spring boxes from 2 separate 2nd generation W126's at the local JY, change the seat skins over to your MB-tex covers, and install them place of your original spring boxes.

They offer superior support and are backwards compatible to the W123 and W116 seats.

http://www.peachparts.com/shopforum/diesel-discussion/352422-diy-%96-pictorial-w126-front-seat-cushions-w116.html

Fabulous writeup!  It will take several re-reads, but very comprehensive, solid work!  So now the search for 126 seats begins. 

Any thoughts on simply installing the 126 seats?  If the 126 box installs onto the 116 rails it seems like it might be feasable.  You mention that there are electrical complexities.  Can you elaborate?  Thanks and cheers,
Title: Re: Another driver's seat repair thread
Post by: raueda1 on 17 April 2022, 04:53 PM
Alec300SD, found lots more info on 126 -> 116 seat swap.  Doesn't look worth it IMO given the control challenge as you posted elsewhere.  Anyway, then I'd lose the OE look of the old seats.  But I found a few junkyard W126's.  The journey continues.  Thanks again,
Title: Re: Another driver's seat repair thread
Post by: Alec300SD on 17 April 2022, 05:08 PM
The spring box fits into the seat bottom frame which attaches to the seat rails.
The W126 seats bottom frames and seat rail widths are wider that those on a W116 and will not fit without  modification.

The W126 seats are electrically controlled by 4 motors (fore-aft, seat angle, seat height, and headrest height) with the controls in the doors.
So you would need to install a harness to power the seats, and have a place to mount the control switches.

The W126 seat back has better side bolster support that the W116 seat back.
I started to convert the W126 seat back to manual seat angle control by swapping in a set of W116 seat hinges.
I lost interest and eventually scrapped the modified W126 seat back, after I realized the headrest adjustment would be lost.
The hinges would also be exposed, as neither the W116 nor the W126 plastic hinge trim covers would fit properly.
With just a spring box swap you retain the original look and controls.

W126 seat back frame (https://imgur.com/bXdEqwb)

W126 seat hinge removed - rivets drilled out (https://imgur.com/BX4FQ77)

Paint prep for installing W116 hinge with manual adjustment mechanism (https://imgur.com/UX6UaDU)

W126 seat back with W116 seat hinge (https://imgur.com/rXnKaeu)

Title: Re: Another driver's seat repair thread
Post by: UTn_boy on 17 April 2022, 05:38 PM
The actual spring box frame is the same between the W116 and W126.  The motors and all of the electric things can be removed from the W126 seats.  Since it's only the spring box you need there is no need to install electric seats.  The only difference is that the early W116 cars had actual coil springs in the frame, whereas after 1975 they all started using ribbon springs.  The seat rails from your W116 will bolt right up to a W126 seat spring frame after the W126 rails are removed.
Title: Re: Another driver's seat repair thread
Post by: orientrot on 17 April 2022, 09:41 PM
I think that Kent's kit works but that you can do a lot better.

I didn't take any pictures unfortunately but have recently done the seat spring swap on 123 seats while also dismantling a set of 116 seats out of a parts car that luckily had had the seat pads replaced at some point with new genuine Mercedes pads. I agree that trying to integrate 126 seat motors/rails because it's a lot of work and if your seat rails aren't piles of rust in the shape of seat rails, you can clean and lubricate them such that they work incredibly well. I should get pictures and type up everything when I do the 123 passenger seat in the future, or when I refurb one of my 116 seats.


Things to note:

Title: Re: Another driver's seat repair thread
Post by: raueda1 on 19 April 2022, 08:48 AM
Many thanks to all, very helpful.  If I can't find a decent 126 then I guess I'll try the kit.  Obviously I'll report on the results...   Cheers,
Title: Re: Another driver's seat repair thread
Post by: orientrot on 19 April 2022, 10:57 AM
Quote from: raueda1 on 19 April 2022, 08:48 AMMany thanks to all, very helpful.  If I can't find a decent 126 then I guess I'll try the kit.  Obviously I'll report on the results...   Cheers,

I probably have a couple spare coil springs and some of the regular flat springs I could send you just for cost of shipping, I think I also have a regular 116 spring box that was a replacement from Mercedes probably 15 years ago if you would prefer that, but obviously that will be a bit more to ship.

Edit: I don't actually have the 116 spring boxes anymore, I remembered that I tried to save them but that the rusty rails had become a permanent part of them due to corrosion and stripped screws
Title: Re: Another driver's seat repair thread
Post by: Jenno1981 on 15 September 2022, 05:31 AM
For what it's worth I went with the MercedesSource kit. Took 15mins to work out how it worked, 15mins to install and stuck some of his foam in as well. Time will tell...

Also, when I took the driver seat out it became evident the previous owner had the seat in for repair of the outer springs. Some heavy duty springs put in on the outer side. They were so heavy duty it caused the driver to lean to the inside and.... collapsed the springs on the inside 😔
Title: Re: Another driver's seat repair thread
Post by: 3l33ter on 18 December 2022, 05:10 PM
I installed w124 seats into my w116 280S. For the passenger seat, I reused the w116 rails and it was fairly easy. For the driver side I went crazy and modified a w126 power seat rail to work, but never mind that. I went with w124 seats because my w116 seats were really soft and squishy (even the back) so I wanted a totally new(er) seat.

Here's my thread. It's long, but maybe the pics would help you see how things look inside the seats.
https://forum.w116.org/interiors-and-exteriors/installing-w124-seats-into-my-w116-technically-it-is-possible/
Title: Re: Another driver's seat repair thread
Post by: john erbe on 06 March 2023, 02:53 PM
Im about to start the 126 to 116 rear seat swap. The frames are different. First step will be to get quote from upholstery shop to put 126 skins on 116 frame. I'll keep you posted.
Title: Re: Another driver's seat repair thread
Post by: john erbe on 24 March 2023, 02:58 PM
Update. Decided to go with/attempt rear seat from 126/420 SEL. Upholstery pattern of rectangles matches Recaros in front. Work in progress.
Title: Re: Another driver's seat repair thread
Post by: raueda1 on 24 March 2023, 08:03 PM
Quote from: john erbe on 24 March 2023, 02:58 PMUpdate. Decided to go with/attempt rear seat from 126/420 SEL. Upholstery pattern of rectangles matches Recaros in front. Work in progress.
pictures!
Title: Re: Another driver's seat repair thread
Post by: john erbe on 25 March 2023, 03:56 PM
Raueda

The black (steel) bracket I was fortunate enough to grab from a 450SEL at wrecker and is the outside one with the eyelet at bottom for the screw fixing to chassis. The aluminum is off the 420 seat. My simple brain tells me that making the swap or changing the position of the bend in the 420 bracket will work. Regarding the bottom, I think there is enough material on 420 skin to have it moved onto the 6.9 spring box.
Title: Re: Another driver's seat repair thread
Post by: raueda1 on 19 April 2023, 10:19 AM
I'm prepping for the seat job. It seems like front seat back cushions are easily available from the usual suppliers.  W116 seat bottom cushions seem to be nonexistent, though GAHH and others have W107 bottoms.  I assume that they're not interchangeable.  Or are they?  Also, can anybody confirm whether W123 cushions will fit the W116 frames?   Anyway, if anybody knows where to get bottoms it would be great.  Thanks and cheers,
Title: Re: Another driver's seat repair thread
Post by: rumb on 19 April 2023, 04:50 PM
Dave,
Did you miss this one?:

https://gahh.com/interiors/seat-pads/seat-pad-1974-1982-mercedes-fnt-bottom
Title: Re: Another driver's seat repair thread
Post by: ptashek on 20 April 2023, 02:14 AM
Available from KHM
https://cabrio.de/de/notsitz/polster-verkleidung/mercedes/116/sitzauflage-116-detail
Title: Re: Another driver's seat repair thread
Post by: raueda1 on 20 April 2023, 09:26 AM
Quote from: rumb on 19 April 2023, 04:50 PMDave,
Did you miss this one?:

https://gahh.com/interiors/seat-pads/seat-pad-1974-1982-mercedes-fnt-bottom
i DID miss it.  I've seen that page before but couldn't find it on most recent searches.  Thanks.  Will order today.  Cheers,