As many of you know, I don’t own an Eos. This makes it difficult to provide practical advice based on my own experience with the car, as I do in the Phaeton forum. The staff at my VW dealership (Volkswagen Richmond Hill) follow activities in the forum, and when a customer called to say that his Eos had a water leak, the service manager at my dealer invited me to come up and watch the problem-solving process.
The Eos with the water leak was the first Eos my dealer sold. It was delivered to the customer only a few days after the Eos went on sale here in North America. It has a fairly low VIN (in the 7,000’s), which suggests that it was probably built sometime in the summer of 2006. This is noteworthy, not because there is anything unique about a low VIN, but because the car is now 8 or 9 months old. This is certainly more than enough time for the seals on the car to dry out.
The owner of the Eos dropped it off at the dealership, and the first thing the technicians did was to have a look at the windows and roof to make sure that they were all operating smoothly and properly, and that all the measurements (especially the reference lines at the top of the window glass) were within specifications. No problems were found. The next step in the troubleshooting process was to carry out a ‘baseline water test’ to determine the extent of the leakage. The dealer principal sat in the driver seat, the windows were closed, and the car was flooded with large volumes of low-pressure water from a rather large hose in the wash bay. After about 30 seconds, he started honking the horn, and when the water was turned off, a very wet dealer principal emerged from the car. No doubt about it, the car leaked.
The leak manifested itself at the front left corner of the windshield, where the roof touches the top of the windshield. None of us knew where the water was getting in, but it was clear that the water was ‘getting out’- in other words, dripping into the cabin - at one specific location.
We all put our heads together to try and determine what the facts were. They were as follows:
1) The car was almost 9 months old, even though it was only delivered to the customer 5 months ago.
2) No-one had ever lubricated the rubber seals on the car.
3) The windows and roof all appeared to work properly, except for some deformation (pinching) of the seals on either side of the sunroof. This deformation appeared to be caused by the sunroof panel binding on the roof seal, and pulling part of the seal downwards.
4) All the technicians had been to Eos training.
5) All of us had read all the technical bulletins (TB’s) issued for the Eos.
6) None of us had ever read the owner manual.
7) No-one wanted to start any kind of dis-assembly. We wanted to try the ‘least invasive’ solutions first.
So, after we had all read the '3.2' section of the Owner Manual (this is the "Tips and Advice" section, and there is some really good information in there), and after some discussion, it was decided that since the owner manual suggests on page 25 of section 3.2 that the roof seals be lubricated with VW lubricant part number G 052 172 A1, maybe it would be a good idea to start by doing exactly that.
We ordered three bottles of lubricant. None of us knew how much would be needed, but we knew that the bottles were pretty small. Because the dealer principal was still wet from the baseline water test, he had no disagreement at all with the technician’s decision to order three bottles of lubricant. Because the lubricant would not arrive until the next day, we asked the PDI person to do a thorough detail of the car, to ensure that there was no dirt or other external influences on the car.
The next day, the lubricant arrived. We all took turns applying it – the technicians, myself, the PDI person, and some of the sales staff. We made some interesting discoveries:
1) An Eos has two different types of seals on it. Roof seals and the seals that windows touch are made of a different material than door seals or trunk lid seals.
2) These ‘different’ seals have sort of a rough texture, kind of like a cat’s tongue.
3) If the seals are dry (not lubricated), they will be quite hard, not pliable, and will not tightly conform to the window edge when the window is rolled up.
4) If the seals are dry, they have a dull finish, and sort of a ‘white’ luster to them.
5) It is easiest to lubricate the seals on either side of the sunroof if the sunroof is open.
6) It is easiest to lubricate the seal that goes across the middle rear of the roof if the roof is stopped partway through the retraction process, before the front part of the roof begins to lift off the windshield.
7) It is easiest to lubricate the windshield seal if the roof is fully retracted.
8) To lubricate seals at the top of the windows, put the lubricant on your finger, then rub it in.
9) If a seal looks deformed, rub lots of lubricant on it, and keep rubbing the seal until it ‘rehydrates’.
10) If you leave the roof open for an hour after doing the lubrication, the seals seem to suck up any excess lubricant that might be sitting on them.
After we finished lubricating all the seals, we conducted another water test. The results were “almost perfect”. There were no leaks from the roof, but there was a small leak – just a few drops – from the area beside the exterior rear view mirror on the driver side. Investigation revealed that we had lubricated the window seals there with the door closed, hence, we did not fully lubricate the seal – we missed the part that hides behind the exterior rear view mirror. After applying lubricant to this area, we carried out the water test again, and the result was perfection – after 15 minutes of hosing the car, not a single drop of water was found inside.
The PDI person dried off the car, and we noticed that there were greasy spots on the paint where we had unintentionally deposited excess lubricant. The excess lubricant can be easily removed from the painted surfaces with a paper towel and some windshield washer fluid – no fancy solvents are needed. Because the paint is not porous, the lubricant can’t sink into it.
Below are a whole bunch of photos that I took – hopefully this will explain the procedure better. Many thanks to all the service department staff at my VW dealer for their help making this post.
Eos Owner Manual - Page 25 of Section 3.2 (NAR English Version)
What it looked like before work began
When seals are not properly lubricated, they bind and get pinched, and as a result, do not keep water out.
Visual characteristics of a seal that needs lubrication
This is the stuff to use, simply because this is what the owner manual says we should use.
The alignment rack is a handy place to use to do the work.
Apply the lubricant sparingly, right out of the bottle (clip the top of the spout).
With the roof in this position, you can get the "butt ends" of the window seals, as well as the rear seal that runs horizontally across the roof.
Don't let the roof lift up from the windshield - otherwise, it will come back down on you!
Don't forget this seal.
...but, DO NOT LUBRICATE the fuzzy seal that touches the trunk lid.
This seal is obviously different from the others - it is fuzzy, not rubber.