It's typical, when you're miles from home and your tool kit, something has to break! I was lucky, this happened on the way home from Cornwall this week, not a show-stopper, but nevertheless it caused a ceremonial 'DOH!'
Basically I started to wind down the window on the offside front door, however the glass decided to remain 'up' at the top of the door momentarily, and then it dropped down in its channel. I've seen this plenty of times on other VW models so I knew exactly what had happened - the glass had become detached from the lifting mechanism. With the door open, I was able to move the glass back up to its closed position and then wind the mechanism back up to keep it in place for the journey home. I don't think I've ever made such good use of the quarter light window before and actually it proved very pleasant on the warm trip back along the A303.
So back home I stripped the door furniture off and as I suspected found the window lifter channel on the regulator empty of glass:
I took the lifter channel off via the two 10mm bolts and as suspected found the seal that grips the glass to be dirty and weak. This happens over the years - water goes down the glass into this seal and eventually weakens it. You shouldn't expect to see this on a relatively new Kombi, but if yours is almost a Classic Kombi like mine, you may experience this failure sooner or later.
So a quick trip down the road to see the boys at Custom and Commercial, I came back with a new lifter channel seal for under £3. You could clean up the old seal and try to revive it but at this cost I elected to replace. The new seal comes longer than the old, so you slide it into the metal lifter and then trim it to fit.
WARNING: ADULT CONTENT APPROACHING!
To enable the glass to slip into the new seal you need a lubricant of sorts. You don't want to use something like Fairy Liquid as that will attack the rubber seal. Best bet is a water soluble lubricant such as KY Jelly. I'll say no more on that.
Refit the lifter channel but only do the bolts up hand tight. Lower the glass into the new seal ensuring it sits in the centre of the 2 sides of the seal. You won't be able to get it to sit down fully in the lifter channel at this part.
Now using the window winder handle (removed during stripping of door furniture) gently wind the mechanism upwards - the glass will go up and eventually get trapped at the top of the door. At this point continue to wind the handle up - all being well the lifter channel is now gently forced onto the glass and the two fixing bolts appear in the centre of the access holes along the top of the frame of the centre section of the door. Now tighten these up fully.
If you now wind the window down, the glass should go down and when you see the lifter channel in the lowered position, the glass should now be fully gripped by the rubber in the lifter channel.
Finally, use the opportunity of having the membrane folded back to grease the window regulator and spray some white grease onto the door lock mechanism. Check all the bolts/screws are tight and then re-stick the membrane to prevent water entering the cab area. (I used quick drying upholstery adhesive via a small paintbrush.)
Refit all the door furniture and wait for the other side to go - except when it does, fixing it will be a piece of cake because you've already done it once!