Manual Sunroof opening

[kru0042]

Gentlemen,

I succeeded in manually opening the sunroof on my '78 450 SEL today. I used the little copper coloured adapter and a socket and she opened up. After cleaning up the rails, etc. I still  couldn't  coax it open with the electric switch. As I  went to close the sliding roof up again, the flat pin  insert sheared off. I just got a smaller socket and succeeded in finishing the job of closing up the roof. I  assume the adapter thing is designed to fail if too much torque is applied so as to not over stress the cable etc.  These little fittings seem hokey to me by MB standards. I seem to be jinxed by the sliding roofs on all but one of my three 70's era Mercedes. The online manual seems a little vague in terms of basic troubleshooting of the sliding roof... or perhaps I am somewhat thick.

How can I best determine which component is causing the  failure of my electric roof. The motor, gear box mechanism, cable, switch etc. ?? Helllllllllllllppppppppppppp!!

Thanks

Darcy

[TJ 450]

I have the same problem on two roofs. In these cases, it is the cable binding and so I'm fairly certain they should be removed and lubricated/replaced.

A way to narrow down the problem would be to disconnect the cable from the sliding part of the roof, and try and slide it manually. If it moves easily, it must be the cable/transmission.

I'm pretty sure those adapter keys are pot metal... shearing at a certain torque sounds reasonable.

Tim

[kru0042]

Thanks Tim.

This gives me something to work on. Eventually, I'll be an expert on the subject.

Cheers,


Darcy

[Squiggle Dog]

This is why I am converting my sunroof to manual. Haha.

[Big_Richard]

the sunroof requires regular maintenance like many other mechanical parts of the car.

It requires periodic cleaning, inspection and lubrication, which would of taken place when the cars were new.

A well maintained sunroof in good order will move effortlessly by the motor back and forth and its torque limiting clutch will never activate during operation unless at the extent of travel in either the open or closed position.

Its also essential to use a decent lubricant that doesn't solidify, harden or turn to glue in the presence of water.

[flutes]

MT any recommendations on lubricants for the various parts of the sunroof?

[Ultimation]

I'm interested in those lubricants, too. I wonder, though, what would be causing mine to open just fine, but not close? I can close it, but it takes about 5km of driving. I have to press the button about fifty times and it just slowly eeks forward.

[nathan]

Darcy,
this is unfortunate for you. the roof has only been an issue on one of our 70s cars (3x116s, 2x123s) with rooves. the easiet way to disconnect the cable might be to pull the sunroof lining off from inside the car (you pry between the roof and the lining) by undoing the several little clips at the front. once these are off the lining pulls forward.  then you will be able to see where the cable attaches at the back of the roof. there is a single little clip which pulls down. once out, the cable will be free and you can trial the roof movement. does this sound reasonable to everyone else?
nathan

[WGB]

Remove the cladding on the left side of the boot to expose the motor and the wiring connector.

If you get no power to the motor when you use the switch it must be either a fuse or the switch - test with a volmeter or a small lamp..

You can easily test the motor by jumping direct from a battery - it will either work or not work.

If the cable is too stiff the clutch at the motor end will slip but you will hear the motor work and the clutch click.

The metal hatch is supported by a number of spring loaded plastic "Sliding Jaws" if these are broken you will get friction but you will still hear the motor work and the clutch clicking - the complete set from Diesel motors cost me $78.

Here is the correct lubricant as recommended by Mercedes Benz "Gleitpaste" - very expensive - AUD$200-300 from the dealer



Another trick for young players is that the motor might hum and some mechanical noises like a clutch clicking might be heard but what has happened is that the gears have worn on the motor shaft or more likely on the cable itself.

The first simple attempt at repair if this is the case is to pull out the cable from the sunroof end (check the workshop manual on how to do it) by disconnecting it and using the motor or hand cranking it forward, lubricate it, and then feed it back in turned 180 degrees so that the motor gets a fresh set of teeth on the cable to work with.

[Ultimation]

I didn't get the official Mercedes brand, but I bought some good lubricant to make the sunroof glide. I ended up taking the whole thing apart (don't we always?) before it was all said and done because there was a lot of corrosion that has built up through the years. Now my sunroof opens and closes freely -- er, almost. It needs a little help closing from all the way back, but we are looking much better than before, now.

Since I have so much of this stuff left over, I suppose I'll take off my door panels and grease up the windows, too!

[kru0042]

Gents,

Thanks to all who offered their input regarding the sunroof. I am well on the way to getting it functioning properly.

Cheers,

Darcy