Sunroof is hard to latch closed

[300TD1982]

EDIT: This is a W123 300TD, 1982
EDIT 2: It's a manual sunroof

My sunroof slides back and forth pretty well, and it's pretty easy to open, but latching it closed takes a lot of force. Enough force that I'm afraid I'll break something. It's a lot easier if I push upwards on the sunroof while latching it, but surely that's not what M-B intended.
Is there something I could lube or bend or replace to make this easier?
Thanks in advance for sharing your wisdom.

[Junkman]

Assuming you have the manual sun roof:
You will be removing the sunroof to understand how it works. Pull the interior piece. It covers the latching mechanism. Towards the back, there is a bar that moves outward when you twist the handle to latch it. There are rollers on the ends that roll up on what looks like small wedges on the side of the car. These wedges have screws that are height adjustments for the back of the sunroof. The bar itself has a length adjustment.

You want a combination of length adjustment and height adjustment that closes the roof without to much effort and gives proper height and holds the roof when opened keeping it from sliding forward when braking.

Descriptions seem clear as mud. You will have to take the roof out to understand. The FSM has crappy pics that help (sort of). Clean the drains and lube the tracks while you are investigating. arbor freight sells a small drain snake that works for this.

The PO of mine didn't clean the drains and 1 floorboards needs to be replaced and there are rust spots where the drains exit near the back.

[Rogviler]

On mine the culprit for both difficulty in sliding and in latching was the vinyl covering, the "mini headliner," if you will. I had better things to do than figure out a way to fix it, so I left it off for the time being. May not be your problem, but you'll probably be removing it anyway so that's something you can test.

[280EZRider]

The latching bars that have a rubber wheel on the end are held in position against the panel on each side, left/right, by a retainer that has a piece of spring steel that presses against the bar. After the lubricant wears off, it becomes hard to move the bars, closing and opening. MBZ makes a special lubricant for this, however I just used 3-in-1 oil the last time and for the last 3 years it is still satisfactory.

Also the upholstered piece just hangs in place attached on the front side, with the rest rubbing against the slides. The edges hold a specific curve to them and can be bent slightly to create either more or less resistance, thus changing the amount force you need to move the roof back and forth.

[Rogviler]

To clarify, my vinyl panel was causing issues mostly because it was saggy and coming apart at the edges so that the vinyl was getting jammed up in the slides and such. I'm sure it worked perfectly fine when new.

[300TD1982]

Thanks all. I read into how to pull the sunroof and it doesn't look too hard, and there's no rain forecast so this is a good time to do it.


Any suggestions on where to find small amounts of the special grease for the rails?

[vwnate1]

I hope you take pictures and write it up .

I too have a manual sun roof on my TD .

[Junkman]

The rollers on the arm that latch the roof are metal on my 85TD. That may mean that the rubber has come off and is MIA. I had to adjust the length of the arms. Be sure to use a magic marker to indicate your starting point in case you want to start over.

I found that too loose and the roof would slide closed when braking. Too tight and latching was difficult. The arms have teeth on the inside that engage with the metal piece above. You can have the roof in place, loosen the nut on 1 side and turn the latch to shorten the arm a little. Tighten the nut and do the other side. Repeat until the roof slides and locks in the open position.

I was ordering parts from MBOEparts and found the height adjusting screws are still available for very few dollars as are most of the little pieces for the wind deflector. MBOE is way behind on shipping so you won't get parts in a hurry.

I ran out of the special grease and have used whatever was lying around. Only a very little is necessary. Usually, I'll clean the slide surfaces, minimally apply grease then remove grease until the correct amount is left.

[vwnate1]

You're supposed to twist the handle to hold it in whatever position you want it, sliding shut when you brake is very desirable .