Sunroof is stuck in the almost closed position - Help! Need to remove the liner

Started by karmann_20v, 06 July 2016, 07:44 PM

karmann_20v

Fellows, this is an issue that its at the top of the list of things to do on the 77. The sunroof is stuck closed, about 3 millimeters away from the fully closed position (on the way up). If I push the switch, I can hear the motor spinning fast in either direction but there is no movement on the sunroof. The other bummer is that actuating the manual crank in the trunk yields the same result: no movement, so I'm thinking the cable is either broken or worn, or the teeth on the actuator on the motor are worn, I don't think the clutch is engaged trying to protect the motor/components.

So my next step is to disconnect the cable from the sunroof and start troubleshooting from there, but how do I remove the s-roof liner in the closed position?

Also any other ideas are highly appreciated!

Thanks.

Type17

Assuming that manual cranking is easy enough but ineffectual (ie: the cable isn't seized in its tubing), it sounds like the teeth are worn off the cable in the fully-closed position (more likely than the teeth on the motor-gear being worn) - you could try removing the motor from the tube in the trunk to see if this is the case - this will also allow you to remove the section of tube behind the motor (nearest the rear lights), which will expose the end of the cable, allowing you to pull it backwards, thus opening the roof panel enough to remove its liner. You can then access and remove the cable from under the roof panel and fit a good used one.


Removing the motor and gearbox from the tubing/cable means disassembling the gearbox, so note how everything fits, etc, especially the order and orientation of the gear-sprockets.
'76 350SE in Silver-Green

karmann_20v

Thanks for the suggestion! I was able to open it half way by hand - pushing no too hard on it with the help of another person. I removed the liner and it doesn't look good, the cable is kinked in at least 2 spots behind the s-roof, removed the circlip and of course the cable doesn't want to come out because of the kinks :(

Next step is the removal of the headliner and feed (guide) the cable out. By the looks of it, so far I added the cable to the part order, but I need to assess the tube and also all the sliding jaws. I will also add all the seals for good measure, although they look to be in decent condition.

By replacing all these parts, I guess it would be a good idea to also remove the motor and inspect/clean/lubricate the sprockets - for this step shall I also use the "Gleitpaste" - which is also on order, or something else?

Type17

When you say the cable is kinked, do you mean the cable itself, or the tubing it travels in - it shouldn't be possible for any kinking to occur if the cable is in its tubing.


Note that the cable won't come out if the circlip/pin device at the very front of the rigid section is still in place, but it also won't come out if the motor gearbox is still assembled around it in the boot/trunk.


You shouldn't need to remove the headliner to remove the cable (thankfully, as it's a big job). If the cable's outer tubing is damaged enough to need replacing, you'll need to remove a lot of trim as well as the headliner, so hopefully it's ok.


The gleitpaste grease is only needed for the sliding jaws (it's a silicone-based grease, so it won't be turned to a sticky glue by the sun's heat in the roof area, like regular axle grease would). However, this isn't an issue in the sunroof motor gearbox, so regular wheel bearing-type grease can be used there.
'76 350SE in Silver-Green

karmann_20v

Very good info, thanks again! By the looks of it, it is thankfully (and hopefully) just the cable, not the tubing that is kinked - I took a picture below. I have removed the clip at the front of the rigid section, not the motor/gearbox section... I will try that next and hopefully it will come out.

Here is the mess (Tube on the left is the sunroof guide and looking towards the back of the car):


I think there is another issue that is not very apparent in the picture above, but the tube inside the headliner does not seem to line up with the guide tube on the sunroof and I think that may be the reason the cable kinked the way it did. Is there anything holding the tube in place at the back? (can't see much without removing the liner)

And secondly, while the main reason for all this was to make the sunroof operational, I also wanted to ensure that the sliding jaws are in good shape and I'm afraid there is another problem here; Now with the cable disconnected from the sunroof panel, I am only able to manually open it about 50-60%. Closing it, I don't seem to be able to push it upwards at the end of the closing cycle, to make the back side of the panel flush with the car roof. I did not force the opening or the closing, but any ideas if I can assess/service the sliding jaws and clean up/grease the mechanisms without removing the sunroof assembly?

daantjie

I know you probably don't want to hear this but you have gone this far,  might as well remove it completely and service it properly. Just think how nice it will be once it works perfectly again after doing it once properly  8)
Daniel
1977 450 SEL 6.9 - Astralsilber

karmann_20v

I hear you, Dan! Just one more task to add to the 2 km long laundry list  :'(

Type17

That photo is weird - the cable should be covered by tubing all the way from the motor to the roof panel - it shouldn't be possible for the cable to be exposed like that, otherwise kinking like in the photo is inevitable... is there a part missing?
'76 350SE in Silver-Green

karmann_20v

I have no idea, although the picture was taken with the roof closed and the portion that is not covered by the tube is the same length as the sunroof retracting distance. I am not sure whether there is anything missing, maybe someone else can chime in.

I found this picture and it appears that the tube starts way back to allow for sunroof clearance in the opened position:

UTn_boy

The end of the tube that the cable resides in ends at the rear edge of the sunroof opening.  This tube also goes through the rear of the sunroof frame, and is held in with two 6mm sheet metal screws.  Judging from the picture you showed us, it looks as if your tube is either missing or is bent so badly we can't see it.  Either way, you're going to have to remove the headliner an the whole sunroof assembly/frame.  I just don't see any way around this.  What makes things worse is that neither the cable or the tube are available any longer. Even when you do find a used one, you have to take into account whether or not the one you find is for a long or a short wheel base car.   
1966 250se coupe`,black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3,papyrus white/dark red leather
1975 450se, pine green metallic/green leather
1973 300sel 4.5,silver blue metallic/blue leather
1979 450sel 516 red/bamboo

karmann_20v

Thanks UTn_boy, the headliner removal is next on the list (hopefully will get it done tomorrow). Once that comes off, I will be able to see what's inside and post some pictures as well.

I just placed an order for the cable (1167800089 - applicable to SEL models), this place claims to have stock. I'll probably find out on Monday whether they are shipping a package to me or refunding (hopefully not the latter).


karmann_20v

Some progress and mostly bad news for me. Saturday, I removed the sunroof assembly from the car. Procedure was straight forward based on the writeup I found on another forum with supporting pics. The headliner trim pieces also came out without a fight. Good!

Here is what I found: the rigid metal tube is there, however it somehow lost the bracket that is supposed to keep it bolted to the rear of the sunroof assembly. Some backyard mechanic attempted to fix it by improvising a bracket, solution failed most likely soon after implementation therefore destroying the cable (see the cable picture a few posts up)...

The good: there is minimal surface rust on the pan, close to the draining holes. Also, the sliders appear to be in decent condition, aside from me breaking one.
The bad: California sun beat down on this car for 37 years, meaning that the 4 drain hoses were so dried up and welded to the metallic drains that they all broke as soon as I touched them.
The ugly: By the looks of it, I need to replace the tube and some sources point to the rear windscreen needing to come out (any ideas if this is required)?

So far, I ended up ordering these parts:
-All sliding jaws (13 pcs) - awaiting confirmation on delivery
-Sunroof cable (apparently NOS, still awaiting order confirmation from the slow German Parts LLC cust svc.) Have a good used one lined up locally as a back up
-Sunroof tube, found it used locally
-Sunroof paste
-Sunroof Foam seal - awaiting confirmation on delivery
-Front and rear sunroof seals - awaiting confirmation on delivery
-Sunroof seal brushes - side- - awaiting confirmation on delivery

Still need to figure out the drain hose situation, but I have at least 2 weeks before the other parts show up and I can reassemble everything. Any suggestions on where to source the tubing and any tips for replacing?

Here are some pics:
What the tube bracket should look like:

The tube on my car:


"improvised" bracket:


As you can tell, this is turning out to be a very frustrating chapter, hopefully once I get everything installed I won't have to worry about the sunroof for another 37 years.

daantjie

Cannot help much but aren't you glad that you decided to drop the whole assembly?Now at least you can fix it right and once only 8)
Daniel
1977 450 SEL 6.9 - Astralsilber

UTn_boy

The tubing for the sunroof drains is still available for about $40.00 USD per meter.  Part number 003-997-63-82.  Glad you found the problem, too! 

I'm certain that the back glass doesn't have to come out to replace the drain tubing.  It's not a fun job to replace the drain tubing, but pretty straight forward. 
1966 250se coupe`,black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3,papyrus white/dark red leather
1975 450se, pine green metallic/green leather
1973 300sel 4.5,silver blue metallic/blue leather
1979 450sel 516 red/bamboo

karmann_20v

Quote from: daantjie on 21 July 2016, 09:57 AM
Cannot help much but aren't you glad that you decided to drop the whole assembly?Now at least you can fix it right and once only 8)

True, although I am missing out on being able to drive the car all these weekends and the summer is so damn short here in Ontario... Should be as good as new when it goes back in.