Power seat recline fix DIY

[graat]

Here’s some instructions and pictures to help you get motivated to finally fix the recline feature on your E36 power seat.

Symptom: Power seat no longer reclines. You hear the motor start for a second and then bind

Solution: Replace the broken plastic gear in recline gearbox under seat. BMW does not supply the gear, or even the gearbox by itself – they’ll want to sell you the entire seat frame or an entire seat (depending on who you talk to), so your realistic options are to find an E36 seat in a junkyard and take it apart, or buy a metal one from Duane at Sports Car Recycling in Phoenix 1-800-947-4138. He had a machine shop make metal ones the same dimension as the plastic ones and is making a killing selling them to unlucky bastards like us for $100 a pop.

Use instructions in Bentley to remove seat. You’ll need a big torx bit (T47). Unplug the pretensioner for safety. Lug the seat somewhere where you can put it upside down.

Take black cover off underneath to expose gearbox closest to seat back. Remove mounting bolts from two motors at the opposite end of the gearbox, and pull them from the square shafts protruding from the gearbox. Remove cover from gearbox. (see 3214.jpg)

Remove all pieces of broken gear, and take out the two worm gears that it sits between. The one with the square shaft just pulls out, the other one which meshes with the main recline gear needs to be worked out with a screwdriver. Before you do this, however, put something under the seat back to support it close to the seat bottom, or have someone hold both seat back and seat bottom because when you pull the second gear nothing is holding the recline and the seat will fall flat under its own weight. Having someone hold the seat will also make getting the second gear out easier because the gears won’t be jammed together by the weight of the seat.

See 3422.jpg - This picture shows the first worm gear with the square shaft that connects to the motor (far right), the second worm gear that meshes with the main recline gear, the new metal replacement gear, and my original crappy plastic gear. The circlip fits on the end of the second worm gear after you’ve put on the replacement metal gear.

To get the new metal gear onto the shaft of the second worm gear I had to tap it with a hammer a few times. Slip it on as far as you can get it with your hand and then put it metal gear down on a scrap of wood and whack it until the shaft end protrudes enough through the metal gear to put the circlip back on (probably unnecessary since you’ve pounded it on there).

Put some new grease on the gears and put everything back together. Should look like 3424.jpg

Put the gearbox cover back on, reattach the motors, and reinstall seat into car (don’t forget to reconnect the pretensioner). If you have a 12V DC source handy you can test it before putting it back in your car (red and yellow wires hanging from motor connector in first picture).

[kwl]

any other solutions besides paying 100$ for that little tiny part?

[graat]

any other solutions besides paying 100$ for that little tiny part?

Ultimately you need to replace the gear, or the gearbox. I spent countless hours online trying to find a manufacturer that sells gears that look similar to no avail. I also went to my local junkyard, but they didn't have any E36's (although another guy on BF found one). I emailed a guy that was selling the seat motors on ebay in the hopes that he had the gearbox. He did - but then was too paranoid to mail me the gears out of it because he thought it dangerous to monkey around with something that could have dangerous consequences in a car crash or even cause a crash (you wouldn't want to have the seat collapse because you put things back incorrectly - although, the broken gear isn't what's holding the seat back up, its that "second worm gear" that I talk about above).

You may luck out and find another source for the gear, but I eventually gave up.

[brendonm]

I've been doing a lot of research on this -- my driver's side seat back on my '96 328i sedan stopped reclining and moving forward. When I use the seatback switch on the side of the seat, I hear the motor going but nothing happens. I assume this is the problem...

[graat]

sounds like it! good luck.

[japdlp]

I just did this job the other day and I highly recommend you buy/borrow a set of Torx bit sockets for the job. You will need T20 and T25 bit sockets to get all the bolts for the motors and the transmission. Ideally they will be 1/4" drive since the area around the bolts is tight. You might also need a swivel adapter and a short extension for the hardest to reach bolts.

There isn't much room to work in there and you can waste a lot of time jacking around with torx screwdrivers and allen wrenches. You can waste even more time if you strip out one of the bolt heads trying to use an allen wrench. Ask me how I know... As it turns out, I had the correct torx bit sockets in my toolbox the whole time. They made the reassembly process MUCH faster than disassembly. This job would have been a cinch if I had used them from the start.

I got my replacement gear from Jeff @ odometergears.com and it worked great. It was $44 shipped.

Best of luck.

[Yabiah]

Fixed my passenger seat recline last week.
I got my replacement gear from Jeff @ Odometer Gears LTD and it worked great. I had him overnight it, $64 if I recall.

[el_bobbo]

is the gear assembly the same for the front-to-back motor as it is the receline?

my passenger seat reclines, but will not move forward. i don't even hear the motor grinding.

[ZONDERVANUS]

I replaced the gears myself... it was a cinch.. the hardest part was getting the cover back on and working outside in the rain.. sheeesh

[Shivan000]

My seat reclines fine, but won't come back it. I assume the problem is still in the gearbox, but it doesn't sound like its the gears talked about here. What could it be? Do I need a whole new gearbox?

E36 by the way.

[ZONDERVANUS]

any other solutions besides paying 100$ for that little tiny part?

I got mine for $44.00 from odometergears.com
and it was easy to install myself.. less than 30 minutes.. I believe there is a DIY on this site.

http://www.odometergears.com/subpages/bmw.html

[k2cane1950]

Here’s some instructions and pictures to help you get motivated to finally fix the recline feature on your E36 power seat.

Symptom: Power seat no longer reclines. You hear the motor start for a second and then bind

Solution: Replace the broken plastic gear in recline gearbox under seat. BMW does not supply the gear, or even the gearbox by itself – they’ll want to sell you the entire seat frame or an entire seat (depending on who you talk to), so your realistic options are to find an E36 seat in a junkyard and take it apart, or buy a metal one from Duane at Sports Car Recycling in Phoenix 1-800-947-4138. He had a machine shop make metal ones the same dimension as the plastic ones and is making a killing selling them to unlucky bastards like us for $100 a pop.

Use instructions in Bentley to remove seat. You’ll need a big torx bit (T47). Unplug the pretensioner for safety. Lug the seat somewhere where you can put it upside down.

Take black cover off underneath to expose gearbox closest to seat back. Remove mounting bolts from two motors at the opposite end of the gearbox, and pull them from the square shafts protruding from the gearbox. Remove cover from gearbox. (see 3214.jpg)

Remove all pieces of broken gear, and take out the two worm gears that it sits between. The one with the square shaft just pulls out, the other one which meshes with the main recline gear needs to be worked out with a screwdriver. Before you do this, however, put something under the seat back to support it close to the seat bottom, or have someone hold both seat back and seat bottom because when you pull the second gear nothing is holding the recline and the seat will fall flat under its own weight. Having someone hold the seat will also make getting the second gear out easier because the gears won’t be jammed together by the weight of the seat.

See 3422.jpg - This picture shows the first worm gear with the square shaft that connects to the motor (far right), the second worm gear that meshes with the main recline gear, the new metal replacement gear, and my original crappy plastic gear. The circlip fits on the end of the second worm gear after you’ve put on the replacement metal gear.

To get the new metal gear onto the shaft of the second worm gear I had to tap it with a hammer a few times. Slip it on as far as you can get it with your hand and then put it metal gear down on a scrap of wood and whack it until the shaft end protrudes enough through the metal gear to put the circlip back on (probably unnecessary since you’ve pounded it on there).

Put some new grease on the gears and put everything back together. Should look like 3424.jpg

Put the gearbox cover back on, reattach the motors, and reinstall seat into car (don’t forget to reconnect the pretensioner). If you have a 12V DC source handy you can test it before putting it back in your car (red and yellow wires hanging from motor connector in first picture).

[Dub tech]

Wow this is an old thread. Bavarian Autosport sells em for $39.95. It's a ripoff I know for a tiny plastic gear that costs about $1.00 to make, but being the only fix they can price gouge.

[Airbus]

I just did the GEAR replacement. DO NOT buy your GEARS from Pelican parts. They aren't even close in right size. The hole is to small and if you can start it on it will break.
Do NOT try this job without torx screwdrivers. If you do, it will be a LONG and frustrating day. Promise!

[jengah]

For the really tricky hex screw on the bottom corner of the bottom motor - you can use a 6mm allen wrench and put a 1/4" drive hex nut driver on it and that will allow you to get in the tight spot if youdon't have a small enough wrench and ball joint.

Takes about 1 hour if you have all the tools. Figure for 2 hours if you need to wing it a bit.

[ZONDERVANUS]

For the really tricky hex screw on the bottom corner of the bottom motor - you can use a 6mm allen wrench and put a 1/4" drive hex nut driver on it and that will allow you to get in the tight spot if youdon't have a small enough wrench and ball joint.

Takes about 1 hour if you have all the tools. Figure for 2 hours if you need to wing it a bit.

It took me about 30 minutes each side.. pretty simple actually.

[D12monkey]

New on the board here. I'm having problems with my seats. I have an 03 525i and the seats recline and comes forward perfectly. Except one side of the seat doean't move. Anyone know if this problem can be cured with this fix?

Thanks in advanced.

[ZONDERVANUS]

New on the board here. I'm having problems with my seats. I have an 03 525i and the seats recline and comes forward perfectly. Except one side of the seat doean't move. Anyone know if this problem can be cured with this fix?

Thanks in advanced.

Its probably the nylon gears in the motors...

there is a place that you can buy them and these are the best.

Just scroll down on the site of the following link and you will see.

http://www.odometergears.com/bmw.html

[natehack]

REALLY new to the forum, but I had to jump on the chance to get in on this conversation.
Just bought an e36 m3 coupe (my dream car forever) and it is not without its faults.
One of the faults is that the power drivers seat (of course) does not scoot fore and aft. Every other power function works great.
My situation sounds different in that the motor does not sound as if it is kicking in, even for a second like previous posters have said.
Could the whole motor be bad and not just the little, overpriced plastic gear?
Sorry for the hijack, but maybe my question will help others.
Thanks to all.

[ZONDERVANUS]

REALLY new to the forum, but I had to jump on the chance to get in on this conversation.
Just bought an e36 m3 coupe (my dream car forever) and it is not without its faults.
One of the faults is that the power drivers seat (of course) does not scoot fore and aft. Every other power function works great.
My situation sounds different in that the motor does not sound as if it is kicking in, even for a second like previous posters have said.
Could the whole motor be bad and not just the little, overpriced plastic gear?
Sorry for the hijack, but maybe my question will help others.
Thanks to all.

Even when you think its just the motor and you dont hear anything it still turned out to be the gears... when you take apart the bottom and get to your motor cover you will see how much grease there is in there... so its very quiet actualy.

[natehack]

Even when you think its just the motor and you dont hear anything it still turned out to be the gears... when you take apart the bottom and get to your motor cover you will see how much grease there is in there... so its very quiet actualy.

That is a good thing I guess since I can't find a motor for this seat anywhere, are the e36 3series motors same as the e36 m3's?

I'll have to look into the gear, the previous owner was a bit taller and my foot strains to reach the clutch. Thanks.

[Wimpy Ti]

so glad i have manual sport seats -.-

hah free bump!!

[m2pc]

Arg, went to take a nap in my car today and when I went to put the seat back up, it went about 1/2 way and the motor clicked a few times and now won't go up anymore.
All I hear is the motor whirring!

The car is stuck in permanent "ghetto mode" and it's going to be a riot to drive home in.

Is there any way to manually move the seat to the upright position? I'm @ work with no tools!

[Airbus]

arg, went to take a nap in my car today and when i went to put the seat back up, it went about 1/2 way and the motor clicked a few times and now won't go up anymore.
All i hear is the motor whirring!

the car is stuck in permanent "ghetto mode" and it's going to be a riot to drive home in.

Is there any way to manually move the seat to the upright position? I'm @ work with no tools!

nope.

[m2pc]

Actually I did find a way to keep the seat in place while I wait for the new gear to arrive -- with the worm gear removed, you can freely move the seat back.

So set it where you want it, replace just the worm gear, and close up the gearbox. The seat will stay in position and you can drive the car; you just won't be able to adjust it.