[hellmet]

One of the windows on our 15 yr old M800 had started to act up and was creaking on every window roll-up/down motion. When I pointed this out to Bosch they did nothing (which is not unexpected given they did nothing I asked them to).

So, I took matters into my own hands one fine Sunday and decided to get my hands dirty. Armed with nothing but Lithium Grease (bearing grease), Engine Oil dispenser, rags, and an electronic gadget prying tool I began.

(I wish I had more pictures, because these are probably not sufficient)

With the plastic prying tool, I pried open the door's internal cover - you'll hear clear pop sounds as the plastic holders pop-out.




Next, with the prying tool, you'll want to create a gap between the decorative rubber ring and the door crank.



In the gap, insert a rag, and start pulling on the rag from both sides. The clip that holds the crank in place will snap-out and fall on the floor - keep it safe. This is the hardest part of the entire DIY so congratulations you're almost there.




Next, remove the screws on the door handle. The entire door cover will now easily come off. Put that aside.



Use a rag and dust off any dust and grime you can within 2-3 minutes. Do not spend too much time on this, it's not worth it.



Now, get that lube and put it on EVERY moving part you can find. Lock/Unlock using the lever and use the door latches to find what moves and how.




Next, use the door crank and use it to roll-up and roll-down the window. You'll see a whole new set of moving parts and rollers.


Dust off the mechanism and oil all moving parts. Get into nooks and crannies, and apply a decent amount of grease on parts that won't hold oil for long. The oil gets into parts fast and the grease will help the oil stay there and will lubricate long after the oil's gone.



Continue to roll-up/roll-down the window while applying lube/grease until all squeeks and sounds are gone. In my case, this roller had stuck into position and was grinding against metal. After lubing it started to roll and became silent.



Use a rag and wipe all drips and excess grease off. Put everything back in the reverse order.

After putting everything back in, I was surprised by how silent the entire door had become - the pop-out lock mechanism, the keyhole mechanism, the window crank, the internal door latch, and there even was lesser resistance when closing the door.

This encouraged me to take up the same operating for the rest of the doors too - but not until the next weekend

[Leoshashi]

A very nicely explained write-up with detailed pictures. Even I own a 15 year old M800 and this thread will help me extremely. Till date I couldn't figure how to open that window roller. Will try again tomorrow morning, taking your thread as a reference.

Regards,
Shashi

[desideep]

Very good and informative information. I would suggest you to use the Bike Chain spray instead, it does not gather dust and keep the thing lubricated for longer.

[soumobakshi]

There is an easier mechanism to pull out the manual window roller.

When you insert and make a slight gap between the door and the roller, you will be able to visualize the open end of the OMEGA shaped clip which you mentioned as will fall apart. Take a small screwdriver and go the opposite end of this and just a small pull will make the Omega Clip come off its position and it will be an easy job to pull the roller knob out of its position.

I remember doing this multiple number of time in our M800 when i was in college to grease; as in Calcutta rain the levers used to work up a bit and make noise.