Sunroof Blues

[Hagbard]

I have been trying to fix my sunroof but it's not cooperating so I am wondering if there is a strategy or way to put everything back together that I'm missing.

I installed a new chain because my old one was all chewed up and one of the risers was broken clean off: IMG_5033.jpgIMG_5034.jpg

So I bought a new chain but when I took the roof apart again I found that a bunch of the parts were all bent and broken. One of the black, plastic guides was broken in two and the metal frame it attached to was bent to hell: IMG_5035.jpg

So I painstakingly bent all the parts back into place and they look fine. They're all well within what I expect is tolerance. And then I reinstalled everything. I got the sliders lined up in the tracks of the roof, didn't force anything, jiggled the chain so that the metal risers were laying down flat (I think) and slid the roof all the way back so I could feed the chains into the slots and crank them into the gear box.

Everything went smoothly. I even unscrewed the gear box so that it hung loose in the ceiling and I could make sure the chains were lined up evenly before I tightened it up again.

However, when I crank the sunroof closed the right side chain riser is not catching on the black rod it's supposed to catch on. It seems like the right side slides forward faster than the left and it flips up before it catches on the rod.

Should I just slide the roof back and try feeding the chains in until I get it right? Or is there a way to do this right the first time?

I'll see if I can get a picture of what I mean when I say the right side riser is not catching on the rod.

[velotopia]

Oh, lord. I'm about to do the exact same overhaul on mine. Good luck and I hope someone here's done this before that can help.

[Hagbard]

so here you can see the left side chain riser is locking into place around the black bar attached to the sunroof: IMG_5038.jpg

And here you can see that the right side chain riser is not locking into place around the black bar: IMG_5040.jpg

[Hagbard]

My sunroof works!

I took everything apart again, made some minor adjustments to parts and put it all back together again and it just works.

My advice to anyone doing this project: do not get frustrated and force anything. The sunroof parts are finicky and brittle. With the sunroof off, make sure that everything is identical and straight on each side.

With the dark brown metal guide covers on the outward-facing side of the roof removed, the sunroof should sit down on the guides and slide all the way back with little to no force applied. It should just slide like butter. If it doesn't, you have something misaligned. Make sure you leave the chains out and loose until last. And make sure the chains are lined up in their grooves, otherwise you'll have to pull the sunroof back out and align the chains in their grooves.

The "tray" that runs along the back side of the sunroof should be under the chain risers. So fold the tray up to make contact with the underside of the sunroof first, then fold the chain risers up so they sit flat under the sunroof. Then feed it all in slowly and gently into the roof guides. Make sure the chains are lined up with the grooves they sit in. If you've aligned all the sliders and chain risers correctly and you still encounter resistance while you're pushing the sunroof back, most likely one of your chains is misaligned and is gumming up the works somewhere. Just be patient and align everything correctly.

Take the crank off and loosen the gear box so it hangs loose in the ceiling and then feed your chains in so that you can make sure they are even on each side. Then tighten the gearbox back in place and put the crank back on and wind the sunroof gently forward to ensure that you've got it put together correctly. Then reattach the guide covers. Voila!

[sbcrockett]

great job man! glad to hear of the success and thanks for reporting back

[tatersalad]

One of the trickiest things about the sunroof is that the two cables are not the same length. I can't remember which one (passenger or driver) side was longest, but one is a "notch" or two longer. Before installing new cables lay them out side by side to see which one is longer. You will need to get that one started in the gearbox before the shorter one. On mine, IIRC it was about two rotations of the crank, and then started the other side in.

[Hagbard]

One of the trickiest things about the sunroof is that the two cables are not the same length. I can't remember which one (passenger or driver) side was longest, but one is a "notch" or two longer. Before installing new cables lay them out side by side to see which one is longer. You will need to get that one started in the gearbox before the shorter one. On mine, IIRC it was about two rotations of the crank, and then started the other side in.

I found a way around this. If you take apart the crank handle and unscrew the flathead screw that holds the gearbox to the roof, the gearbox will hang loose in the ceiling and you can fish the cables into their slots first and then re-tighten the gearbox back into place over them so there's no hassle with fishing them in just right.

I did it with mine and it worked like a charm.

**Also, my replacement cables were genuine bmw parts and they were both the same length. They did have minor differences from the original ones I replaced though.

[velotopia]

Which guide did you follow to do this work? And, did you have to pull out any headliner? TIA.

I need to get on this sooner rather than later, the panel doesn't sit quite flush so it's letting a lot of water into the side channels. I keep the car pointed downhill to direct water to the drains better and prevent interior splashing.

[Hagbard]

I did not follow a guide. Also, no headliner was removed during this project. It's pretty simple to remove the sunroof. Just crank or push it all the way or about 80% back and remove the covers on each side L & R of the sun roof.
IMG_5031.jpg
They each have 6 small philips head screws (red arrows). The two screws to the far right in the picture hold down a little metal piece that has a nubbin that sticks out to the outward side. This is a guide nubbin:
IMG_5049.jpg
that gets funneled into the chain risers and lifts the riser up when you vent the sun roof (purple arrows):
IMG_5038.jpg
The yellow arrow points to the black bar that the chain riser catches to lift the sunroof up when venting.

I set the little metal thing that sits under the nubbin piece (marked with the turquoise arrow in the first picture) all the way back but take note of how yours is set up and keep it the same (I guess).

Once you remove the 6 screws and the covers from each side, set those aside and then un-crank the chains so they pop up out of their tracks. When you've completely un-cranked them you should be able to pull them completely out with a very small amount of force. Then pull the sun roof 75% of the way forward by hand and lift the front up. Then continue to pull the sun roof forward until you can lift it completely out.

Then just replace the parts. Really all the mechanisms consist of is two black, plastic guides and the chain cables and risers, which you can see in my pictures earlier in the thread. Just be gentle, make sure everything is lined up properly, put a reasonable amount of white lightning grease or similar on the chain and moving pieces and put it all back together.

Don't waste time trying to crank the chains back into place when you reinstall the thing. Just take the crank apart and unscrew that one flathead screw (just to the far right of the opening where the crank was) that holds the gear box in place so that the gearbox hangs loose in the ceiling. Then, once you've lined everything up and have gently slid your sunroof back into place making sure that the chains are properly seated in their grooves, feed the chains into their respective slots until they sit flat. Then reinstall the gearbox and crank and crank the sunroof forward a couple inches making sure that it slides forward evenly. If it does, reinstall the covers removed at the beginning and crank your sunroof a couple times making sure it vents and opens and closes correctly.

That's it!

**Now that I think of it, it might actually behoove you to just take off the crank and unscrew the gear box at the beginning. That way you can push the sunroof back by hand with no resistance from the gearbox and the chains can just be pulled out easily. Your call.
If you have broken pieces in there it may take a lot of brute force to push your sunroof completely open. It took a lot of elbow grease for me.

**Also, beware when trying to re-seat the sunroof that you have correctly seated everything properly before you try to push it back in. If you haven't, it won't sit correctly and you can seriously F-up your sunroof paint because it will scrape along the rough, lower edge of the roof. DO NOT FORCE ANYTHING in this job. Take your time. Smoke a cigarette or take a sip of bourbon to calm your nerves if you have to, and woo-sah your way to a working sunroof.

[velotopia]

Nice tutorial, thanks so much! Will report back once I dig in.

[pommeree]

I'm working from the Blue book and it's kind of ambiguous.
Step 1. Mirrors what you said about removing the guide rail and references the same ~6 screws.


The next step reads, "Press off headliner frame at front and push back." and it looks like they've just yanked down on the vinyl to snap it free.
Is it just as simple as that? Grab and gently pull down? Are there clips? Is it glued?


After that it appears you have access to three nuts on each side securing the lid.
And then it should lift out without taking the frame or mechanics with it.
Also true?


I'm just nervous and hoping anyone who's done this can paint a clearer picture for me.
Thanks!

Here's "Installation" FWIW

[pommeree]

Took a shot at this myself. Here's what I did.
Opened the sunroof all the way and then removed the six screws on each rail
(left-most screw removed before I snapped the pic)



(switched sides) upper-rail removed, cable exposed.


Carefully closed roof to about 5cm


Sure enough, a gentle tug downward on the front edge of the liner popped it free revealing conventional clips-in-holes.
Also, in the dark, you can make out the metal gusset that spans the liner frame pushing out & down.
The frame for the liner was much more substantial than I anticipated.


The liner out and upside down. It was a bit of a wrestling match and I'm not confident I did it correctly.
Note the gusset in the middle has been bent.


From what little I've ready about auto-upholstery, I believe the liner was glued to the center gusset at one point.


Two arms reached from the center of the liner frame to the trailing edge. One had a plastic clip ...


while the other did not ... (uh, oh)


Also, barely visible here is where the (already trashed) headliner was torn in the process. (far left corner in image)
Trust me it's filthy. The photos don't do it justice. But it least until now it hadn't been torn.


The aforementioned "three nuts"


Just a close up of the leading edge, in situ.


Mechanism detail.


Hey! There's the other plastic clip from the liner-arm! WTH?
Little black rectangular piece, dead-center of photo.


Anyway, thar she blows!
Note two guide feet on leading edge. Those are sandwiched between upper and lower halves of the guide rails.
Then the cables work the trolleys that are attached to the back of the panel at the three studs seen here toward the rear.
Foam is still soft, like new! I was so grateful it wasn't a crumbly mess.


Guide foot detail.
Having demystified the sunroof at least a little at this point, one thing I can say you can safely do right now is back the sunroof all the way up, remove the upper halves of the rails and clean out the nasty crap and 30+ year old grease and re-lubricate.
Had I not been so petrified by the sunroof all these years and now seeing what I'm seeing, I wish I had done that ages ago.
Look at that. That's nasty.


This is what artists call "negative space"
"In what way is the passenger confined to the car? Is this image telling us we're 'captive' to our automotive culture? Or is the car the metaphorical shell in which we seek comfort from the conflict outside?"


Trolley detail.
(BTW, I'm making these names up.)


Let's talk about this guy ...
This is a bar or tray that spans the space and slides freely on the tracks behind & independent of the trollies.
It is where the two arms w/ clips on the sunroof liner attach.
Is its job to get dragged back and forth by the liner?
Is its job to keep the liner straight?
Is its job to give the liner something to hold onto when it's scared?
More importantly. How the heck am I supposed to re-attach those crappy clips before/during the process of wrestling the metal frame back up through the hole?
I haven't a clue. Do you?
(EDIT: realoem calls it a "rain gutter" Now I feel stupid. A thin metal tray that follows along the trailing edge of the sunroof to catch the rain and divert it to the troughs on either side! Genius!)

[idarling]

After removing the liner from the sunroof frame it should have been slid back just like if you were sliding the sunroof back. Then remove the sunroof completely. Once the sunroof is gone you slide the liner frame forward again and it lifts right out the top.

[pommeree]

After removing the liner from the sunroof frame it should have been slid back just like if you were sliding the sunroof back. Then remove the sunroof completely. Once the sunroof is gone you slide the liner frame forward again and it lifts right out the top.

Dammit! That makes perfect sense! I knew the #$%^ wresting match I had couldn't have been right!

[SoCalE21]

Thanks for the pics, very interesting.
There seem to be some sunroof experts here.
Here's a minor issue I have:
When I close my sunroof to the position where the crank "click" or "locks" into the "sunroof closed position," the rear of the roof is up about a half inch.
In other words, the sunroof position isn't synched with the "click" on the crank/gearbox. It's a half turn off.
So I can close my sunroof flat, but it's a half turn of the crank off where it should be.
Seems like there should be an easy fix for that, but I'm not visualizing what that would be.

[idarling]

You need to reposition the stop pin bracket circled below by loosening the two screws. It determines when the back of the sunroof starts to lift up. If the rear height is still wrong then you need to adjust the position of the actual sunroof on the triangle shaped rear bracket. It has elongated holes and possibly shims. The back of the sunroof should end up 1 mm above the roof line.
Stop pin bracket.jpg

[SoCalE21]

Thanks.
I did the repositioning of the stop pin bracket, and also the adjustment on the triangle shaped rear bracket.
It's much better, but even when those are adjusted to the max low range of adjustment, it's still a touch too high in the rear. Like 2 mm above the roof line, instead of 1.
Is there any other adjustment?

Also, for anyone looking to work on their sunroof, the way the original poster pulled the interior panel is obviously wrong! Don't do it that way, you'll bend it up and tear your headliner, like he did. The right way to do it is to open the roof 2 inches, pull the front edge of the panel down, CLOSE THE SUNROOF, and push the interior panel rearward into the body.

You can then work on all the sunroof parts.

[idarling]

Thanks.
I did the repositioning of the stop pin bracket, and also the adjustment on the triangle shaped rear bracket.
It's much better, but even when those are adjusted to the max low range of adjustment, it's still a touch too high in the rear. Like 2 mm above the roof line, instead of 1.
Is there any other adjustment?

This is where my knowledge ends other than to suggest looking for shims between the bracket and the sunroof. Its been 20 years since I last had mine apart.

[levifarris]

How does someone go about replacing the chains? And where is a good place to order the parts?