Fixing the Sunroof
- joepampel
- 2 days ago
- 11 min read
Updated: 25 minutes ago
"F*ckery" is something I am far more used to seeing in rusty old British cars which are often inexpensive and purchased by folks who are learning their way around a car. I know; I was one of them. I tried never to be a DPO (Dumb Prior Owner) but there were corners cut at first. It happens.
But when my 911's sunroof jammed I really wasn't ready for what I found. There are two big pieces to this:
The early style sunroof cables are NLA, so owners need to fit the 964 style. These have felt in them which makes them a bit of a tight fit, so the felt usually has to come off first.
You are not supposed to grease the sunroof cables. Perhaps counter intuitive, but the cables and mechanisms are out in the elements and grease just collects dirt, gets tacky and gums things up. It can also liquify in the hot sun and run down on to your headliner.
Prior work adding more sealer made cleanup an arduous process, and there were missing parts.
A helpful gent on the Pelican boards identified that I have cut-down 964 rails and 964 cables. That was a recommended dealer fix at some point I was told. The real miss was that whoever did the work (or perhaps later?) greased up the cables. The rails are ok to use with the later cables, but I am not sure about the guide tube in the rear, that still feels tight. There are some other missing bits I will replace as well.
Potential Parts:
Short section of sunroof seal: 911-564-193-00
Long section of sunroof seal: 911-564-191-00
Rubber seal (back of sunroof): 901-564-905-05
Long felt strip (under wind deflector): 911-564-409-00
Short felt strip (x2): 911-564-409-01
Front Sunroof Guide(x2: 911-564-045-00
Sunroof guide lock plate(x2): 911-564-451-00
Front plastic guide clip(x2): 911-564-433-00
Rear Plastic guide shoe(x2): 901-564-431-06
Wind Deflector Hinge (kickstand): 911-564-127-00
Male Pin for sunroof motor connector: N-017-564-1
Female Pin for sunroof motor connector: Digikey WM1271-ND
Symptoms: First it was a blown fuse, then later the sunroof would not come all the way up in the rear so I pushed it from inside the car. Then finally, the motor whirred and nothing happened. It would not open or close. I could not move it with the crank either. Was it the gear? The clutch? Something else?
The manuals and the Pelican Parts site have some good procedures and photos of what is going on, but I still had a hard time visulizing it all. So I am writing this.
Step 1 is removing the headliner that is clipped into the sunroof. My sunroof was stuck closed so I could not easily get that done. I ended up using a trim tool to find a loose spot and then I pulled the rest of the clips out from there. The clips are only at the front edge of the headliner.
Pro Tip: As it happened, I had a rip in my drivers seat so I pulled it out to go to the auto leather specialist. Having the driver's seat out made working on the sunroof much easier. If you're tall I would defintely recommend removing it.
Once the panels are out you can see the motor and gearbox. They are connected by a rubber "clutch". There is actually some slip built into the gearbox too; there is no "stop" in the system to turn the motor off so over-run in either direction needs to be accomodated.
I used a trim tool to get up between the headliner and sunroof panel since I could not move the sunroof at all, even manually with the crank.
Trim tools are really handy. This one is great for all kinds of hidden clips as seen on doors, bumper trim, etc. The angle made it a good solution here.
Step 2: once the headliner is loose you can slide it back into the roof and out of the way. It rides in a slot that is part of the sunroof tracks. Sliding it back will expose the sunroof guide bolts and the cable guide bolts. (pic above). This is the metal bracket that is a "Y" shape, and inside the Y is plastic so it can slide. There is a plastic sleeve over the end of it. The captive nuts below it rotate and set the resting height of the front of the sunroof. The guide is sitting on a ceiling panel and you can see how those clips work.
The guide with the plastic sleeve (above). It also seems to have grease in it.
The plastic collars around the guide mount "captive nuts" rotate to move the roof panel up and down so it closes nice and evenly. Easy to adjust as needed when you put it back together.
Next, rotate this sping loaded clip out of the way so you can remove the cable guide. It has two pieces, a flat metal bit that locks it in to place and then the actual guide piece that connects to the part that slides along the track. Once the guides and cable ends are unbolted, the panel can come out.
Put some towels out to protect your paint and then slowly move the sunroof panel forwards, up and out of the car. It is heavier than it looks (~12lbs); not heavy, but heavier. Just use caution.
The headliner panel is still in the car here (it rides in a track), but will have room to come out once you loosen the cable track (the long black aluminum guide). I learned during this project that these are the later cable guides (annodized black is a giveaway) and cables (from a 964) which was a recommended fix at some point. There are missing pieces, and then they also greased the cables which is verboten. You can see that the front "stop" point for the mechanism is when the cable glide contacts the middle piece in the track which also supports the wind deflector support.
Remove the guide piece that the wind deflector support connects to. (2 phillips screws) and then remove the 1 screw with small bracket that holds the cable guide in place. Both of my little "kick-stands" were pretty brittle so I ordered a new pair.
Remove the screw and bracket that hold the guide in place (above) & then slide the guide forwards and out of the car to expose your cables and the cable ends. Be careful of the plastic locating pegs in the rear that sit in the guide and then fit into a hole at the back of the roof. They are important, and not sold separately. If they stay in the roof, use some long pliers to get them out.
Here is what the system looks like out of the car. I didn't tuck the cables into their tracks but otherwise it's pretty close to how it sits when installed. That white plastic pin is what locates in the rear of the roof and it gets some body sealer on it before it gets reinstalled.
As I cleaned things up, I periodically checked the cables in the tubes to see how smoothly they would move.
I took the guides inside to the slop sink and scrubbed them clean with degreaser and a toothbrush.
With the guide out, you can see your cable and the "glide" it is attached to that pushes or pulls the sunroof around. Here we have a case where the prior person installed the newer style 964 tracks & cables (felt wound into the cable, and metal ends) but also seems to have greased them. There should not be any grease used on the cables, it just gathers dirt and gums things up. The felt makes the cables hard to pull through the guides so the general advice in older models is to remove it, so I need to take it all apart, remove the felt and then degrease it all. This is why there is beer in the fridge. You cal use an awl to loosen the felt at the "slide end" and then just unwrap it if you are going to remove it. Spoiler alert: I wound up having to remove the felt due to the damage the grease caused.
But first, what broke in the sunroof? The passenger side cable pulled out of its crimp to the glide. Probably because the mechanism was so stiff. I'm lucky the gearbox has a metal gear, and nothing else broke from stress. The gearbox has slip build in to protect it, and a rubber linkage (they call it a clutch) to absorb shocks.
I was able to clear the hole in the slide out with a small drill bit until I could get the cable back in and re-crimp it. I used vice grips to crimp it. Not too much or it may not slide well in the track. After looking at a number of posts on the Pelican boards, this seems to be a pretty common failure point, and a common fix. Some folks not only re-crimp the cable but also add a dab of JB Weld for good measure. New cables are about $500 a pair so fixing the old ones is certainly worth the effort.
Twisting the end back on in the direction that the stranded cable was wound in is what you want to do here. You can see the rear of the height adjustment here, you loosen the screw and move the "nut" portion up or down along the toothed surface.
The cable on the left is worse, but both were pretty greasy and crusty. I scrubbed them in the slop sink with an old toothbrush and degreaser.
I removed the tracks and scrubbed them out as best as I could with a brush, Zep and plenty of hot water. Be careful removing them because they can push against the headliner and those tiny nuts are a pain to get to and there are clip nuts and metal panels athat are sharp.
One of the leads to the motor power plug came off so I needed to order a new pin; luckily Stoddard carries them. It's the same pin used inside the doors, for the oil cooler fan and on the power mirror harness.
The underside of the sunroof panel. (front edge towards bottom) You will probably want to replace the two plastic guides (arrows). There should be 2 felt pads in the rear corners. There are 2 similar felt pads on the sunroof trim panel in the rear corners as well.
Pull off the old seal, and then use the 3M Adhesive remover to clean up the area so you can get a nice strong bond. I used a toothbrush to help with this. Put some rags in the guide channel in case any solvent flows towards the rear. Don't be stingy with the solvent, it can take a bit to get things loosened up. My car had black trim adhesive as well as the yellow/green stuff and it was just trowled on in places. I guess it was leaking. Mask off the roof; any drips or splashes will need to get cleaned of the paint with a little gentle polishing compound or a soft cloth with a little adhesive remover.
The car was missing both sets of felts - the header rail has one under the wind deflector and then there are shorter pieces on each side under the guides (I think, based on the factory parts diagram)
I put arrows pointing at the missing felt strips, and I circled the missing guide lock plates (45) as well as the other plastic guides you should replace while you are there (43 & 49)
One of the leads broke off the harness side of the motor connector (R) as I removed it. I used the connector tool to push out the remaining pin so I can replace it. Its a standard VW/Audi/Porsche connector. Digikey has female pins you can use, and Stoddard carries the male pins that snap into the harness-side of the connector.
The sunroof panel seals had sealer glopped on as well as the original glue. It took a while to clean up. My arrows on the tape are marking where the old seal ends to help me place the new one.
I got the roof panel cleaned up and had a good think about which adhesive I would try out. There were some posts that favored the 3M black super trim adhesive, since the seals are black it blends in better. In the end that point won out for the panel. It gets tacky fast and is hard to brush around accurately as it is very gooey.
I think what I learned quickly on my first go-round at this was:
keep the adhesive on the lower (flat, not round) part of the seal so it stays hidden
work quickly in sections. I marked center on the seal and center on the roof, and then worked outwards, one side at a time, a few inches at a time, level it and then tape it in place.
when you remove your painters tape, do it sideways so it does not pull on the new seal.
I did the rear rubber seal last, and I used painters tape to mark off the borders of it so I would apply the sealer to the panel accurately.
I applied sealer to both the roof panel and the seals, just a nice light coating so it doesn't ooze out all over when you push the seal down.
The top of the seal should not be higher than the roofline. I used a plastic trim tool gliding over painters tape to level it off as I went.
One thing that was tricky is the new fuzzy seal for the rear of the sunroof panel was taller than the old one (or maybe they shrink over time?) so lining it up with the rooftop was trickier than I expected. I used trim tools covered in tape and riding along on tape to try and keep it all pushed down evenly and scrunched against the vertical panel it bonds to.
The pin for the sunroof motor connector came from Stoddard, so I can get the tubes and motor back in place.
It took nearly 2 hours to get both cables fully cleaned up.
After (top) Before (bottom) that was a spot where the felt was not too bad. A lot of it was just mush though.
The sunroof panel after the glue dried. I just marked off the roof center and seal center and worked out from there. (there was a lot more tape on it during the work)
Where the guide tube goes through to the roof cavity. 8mm nut and washer hold the tube in place on that stud. The hole to the left with white body sealer is for the plastic locating pin. Use some new sealer to keep it from leaking.
What the pin looks like, and my broken wire. I stripped it and then needed to take a few strands out to make it thin enough to crimp into the new one.
There we are with the new pin in place.
I remounted the tube and then the motor. Leave the gearbox until last - you want to align the roof panel properly first and then install it. I put it in too early and got to pop it back out.
When you put the trim panels back over the motor and tubes be sure to mount the short one first. I left this all open until I knew it was working.
Putting the guides in. I put the long felt under the wind deflector, and the short ones under the front part of the guides. You need to be a bit of an octopus here since both guides go in together with the sunroof trim panel between them in its track, and the wind deflector shares the bolts that hold down the guides. It all works out though.
Trim panel and guides are in place here.
View looking back on the passenger side. The screw on the far left (top) sets the height of the rear of the sunroof
Where the cable bolts to the panel.
The guide at the front of the roof panel. My car was missing that lock plate (? not sure what it really does) The knurled mounts let you set the height at the front of the panel.
And there it is. Lots of room for improvement; the seal is a bit more uneven than I would like, but it was my first time and I'm glad I could repair the cables and get everything cleaned up so that it works smoothly now.
Special thanks to the Pelican Parts forum folks who have posted a number of great threads about sunroof repairs! I also watched Joe Engineer's videos about his sunroof repair. Links below.
Resources:
3M Specialty Adhesive Remover: Part# 38987
3M "Yellow" Super trim adhesive: Part# 08090
3M "Black" Super trim adhesive: Part# 08008
McMaster-Carr - long cleaning brushes for the tubes: https://www.mcmaster.com/products/pipe-cleaning-brushes/shank-style~handle/low-scratch-tube-brush-sets-with-handle/
Pelican Parts Tech How-To: https://www.pelicanparts.com/techarticles/101_Projects_Porsche_911/85-Sunroof/85-Sunroof.htm
Pelican Parts 911 Forum Posts: https://forums.pelicanparts.com/porsche-911-technical-forum/1174676-tech-topic-sunroof-seal-replacement.html
Joe Engineer's 3-part video about his Sunroof repair
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