sunroof not sliding back

[Zuffenhausen]

sunroof not sliding back, only prop upwards. Any ideas of issue or how to fix?

 

[emerydc8]

I think I would rather attempt a valve job before I would jump into repairing that sunroof. It seems like the most complex, Rube Goldbergish feature on the car.

 

[Zuffenhausen]

I was hoping for an easy fix

 

[JordiC]

Do you hear any noise when the switch is activated?

 

[Zuffenhausen]

it props up and down no problem but it will only go slide back a hair

 

[JordiC]

I'm pretty sure gsxr is familiar with the mechanism. Wait for him to chime in.

 

[gerryvz]

There is no easy fix when it comes to sunroofs. They are complex and difficult to fix. One of the only systems on the car that I have (to date) sloughed off on my mechanics to fix. The last major sunroof work I had done (replacing lifter mechanism on my 560SEC) I had done by my mechanic in Portland, and IIRC it cost me over $1,000. The parts are not cheap, at least for the 126.

Have you tried "helping" the sunroof to slide backward? Often times it can be lubrication that is an issue, but your situation sounds more serious than that.

Sunroofs are best left to the experts unless you really know what you are doing....

Cheers,
Gerry

 

[gsxr]

It could be as simple as the clutch needing to be tightened slightly... this may be due to lack of lubrication. Try to "help" the sunroof slide with your fingers. If it will move back with assistance, clean & lube the rails. To do this properly requires having the sunroof fully opened, and then disassembling things a bit for a proper clean & lube. A major service requires disassembling the sunroof and replacing all the felt pads on the sliders, and lubing everything with Gleitpaste. As long as nothing is broken, the sunroof mechanism isn't quite as daunting as most people think, but you MUST follow the factory procedures during R&R.

If either lift arm has broken, that is bad. This generally manifests itself as the sunroof popping unevenly, or retracting unevenly and binding. MB improved the lift arms circa 1988 and it's not common for the 88-up mechanism to break. The 86-87 were much more failure prone. Photos of the R&R on my 87 300D are here:
http://www.w124performance.com/images/W124_sunroof/

 

[Zuffenhausen]

thanks for the input guys. Dave how does one tighten the clutch?

 

[Zuffenhausen]

actually it moved back by "helping it" so what do I need to lubricate?

There is no easy fix when it comes to sunroofs. They are complex and difficult to fix. One of the only systems on the car that I have (to date) sloughed off on my mechanics to fix. The last major sunroof work I had done (replacing lifter mechanism on my 560SEC) I had done by my mechanic in Portland, and IIRC it cost me over $1,000. The parts are not cheap, at least for the 126.

Have you tried "helping" the sunroof to slide backward? Often times it can be lubrication that is an issue, but your situation sounds more serious than that.

Sunroofs are best left to the experts unless you really know what you are doing....

Cheers,
Gerry

 

[gsxr]

A full clean & lube would be as shown in this FSM document:
http://www.w124-zone.com/downloads/MB CD/W124/w124CD1/Program/Maintenance/94_95/7730.pdf

Additional procedures are in the FSM here:
http://www.w124-zone.com/downloads/MB CD/W124/Index/Groups/77Roofs.htm

The photos at my previous link should help. Only use the Mercedes Gleitpaste for lubricant. Remove ALL traces of old lube.

 

[Zuffenhausen]

ok after cleaning, decreasing, and adding a can of lithium spray lube it works about 95%. I should probably get a new seal for the sunroof as it does seal maybe because the seal is not as pliable as it once was

 

[silveralfa]

I have the exact same problem. The good news, if you will is that the entire sunroof unbolts from the car as a unit, although the headliner needs to came out. I bought a complete sunroof to play with to see about fixing my stuck one. Seeing it as a unit makes it clearer how it works. I can endorse the idea of pushing to help it open. I believe mine got stuck because it was rarely used by the previous owner.

 

[Allgonquin]

I see that Zuff used lithium spray lube, and I see that the FSM refers to "slide paste" - is there any magic monkey snot which is easily available and recommended or should I suck it up and order what the factory says?

And another question. BMW used to recommend something called "Gummifledge" for lubing/coating rubber gaskets to keep them from sticking. On my '95 diesel, the trunk gasket sticks something fierce if I have not opened the trunk in a week or two. Any recommendations for something like this?

TIA...

 

[gerryvz]

I have a lifetime supply jug of the proper "Gleitpaste" (sunroof grease). If you PM me your address, I'll send you a tube with enough grease to lube 3-5 cars' sunroofs, for free.

Before getting the Gleitpaste I used to use Lubriplate grease, which worked just fine too.

Cheers,
Gerry

 

[Ricardo]

Figured I would add it to this thread vs starting another one...

New owner of 92' 500E and the sunroof seems to studder when opening and closing... no unusual noises.. just that studdering..
And gerryvz, I will PM you if that offer for some lube is still available

thanks
Ricardo