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Rear window seal removal and refitting

Started by daantjie, 05 August 2017, 07:53 PM

daantjie

Hi guys

Okie dokie, going to try and lay out the steps I took to remove the old seal and replace with a new one on my 6.9. 
Full disclosure, I used an URO seal, which I know fills some with horror, but after some research I went with the URO based on some positive reviews from well respected members here.
Also, I did this all by myself, which I do not recommend if you have a competent helper with steady hands around, which I did not.
I decided to back the car onto the drive under the carport, which is on a fairly steep incline.  Thus the rear glass was on the higher end of the incline.  I did this as I was hoping that gravity
will help me in "adding weight" to the glass, to enable me to pull in the seal with the "rope method", as usually you need a helper to gently and with firm, even pressure push on the glass
from the outside, while you pull the rope from the inside.  I have read that the car must be on a level plane so as to ensure the chassis is not under any stress or load, so the jury is still out on my approach.
Thus again I would advise to have a helper.

Here is a pic showing the old seal in situ, with trim removed:

Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

I call my method the "hybrid method" as I took many tips from this and other forums to come up with my own "secret sauce" if you like 8)
Follow the service manual in removing all the following interior trim.  I felt it was best to completely expose the inside of the seal, thus, removed:
Side roof panels (held on by the grab handles)
Centre panel between the side panels (houses the rear dome light)
Hat rack/parcel shelf (obviously you need to remove the whole rear seat)
Stiffening section at bottom of glass.
Side panels housing seat belt channel

Now you will see the complete inner seal, take note of the LHS and RHS wires for demister - you need to carefully remove the RHS one from the earth/ground connection
behind the insulation (right next to the round plastic cover where you access the shock top mount)
LHS one unplugs in the same area on the LHS.

Some pics of inside of the seal:

Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

At this point I need to stress safety.  Please ensure you use eye protection as well as gloves, as you will be working with sharp blades, and old sealant and rubber flying off potentially in all directions.
Also, there is of course the risk that the glass might break, and this can result in serious injury so please think safety for both you and any helpers.  Not worth losing an eye, finger or worse for a new seal!

This is also where my method deviates slightly, as I decided to cut away the exposed rubber on BOTH the inside AND outside of the glass.  I was lucky in that the seal on the outside had completely shrunk and pulled
away from the trim.  Thus once the chrome trim was removed, the outer rubber section sat well proud of the glass.  So for the outer section, I was able to cut/pull away the seal from the glass, with some gentle use of a side cutter.
Some parts would peel away in long strips, and I was surprised that beneath the crusty exterior the "lower" part of the rubber was actually very pliable.  Some pics of outside cutting away:

Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#3
Next I moved to the inside of the car, and I used a small box cutter (Stanley knife), with a long blade (pushed out as far as you can).  This gives you a very flexible blade, which is
important as you need to keep the blade parallel to the glass as you cut (blade points to the glass but downwards).  Use some pliers to grab the seal whilst you cut with the other hand.
Again I was lucky in that my seal was still quite pliable so the cutting on the inside was a breeze.  After cutting on the inside:
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#4
There is still enough of the seal material left at this point that the window should still sit in place, but essentially is it now free of the body.  Again as I was alone, I chose
this method to make it easier to release the glass.  Normally folks only cut the inside, then push evenly from inside, whilst a helper or 2 catches the window on the outside.

I now pushed very gently from the inside, and with very little pressure the window released from the seal remnants.  But seeing as the seal is still glued to the body the glass should not "drop into" the car.
By now the top of the seal had dropped down into the car slightly, thus I was able to now go outside, and slide my gloved hand under the window, and lift it clear of the body.
Not to blow my own horn too much ;D but I am a fairly big guy and again if you are not steady of hand and able to lift it clear in one go then this method is not for you.
Also, make sure you have a thick quilt or blanket on the trunk so you can pivot the glass and then rest it gently (curved side down) onto the blanket. 
Now this is where you pull the electrical cords for the demister free of the old seal.
Now you can reposition your hands,
and carry it to the bench.  Again, steady hands, clear path and no distractions!  I was surprised at how heavy and unwieldy the glass actually was!
Here is a pic of the glass, curved side down on my "bench" (dining room table with another thick blanket)

Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#5
I gave the window a good cleaning with some Windex and paper towel.  Again be careful when turning the glass over on the blanket.
Now this part really challenged me :o  Getting the seal onto the glass was murder.  I used a mixture of 50/50 dish soap (Sunlight liquid or similar) and water and spread this
inside the rubber channel where the glass sits.
Also, at this point you need to cut new holes into the channel for the demister wires.  Use the old seal as reference
Not sure why I struggled so much but eventually I got the seal onto the glass.  Next you add the rope into the channel where the pinch weld will go.  I used a 5mm diametre nylon
rope and I applied a light coat of dielectric grease to the rope before I pushed it into the channel.   This part was a breeze compared to the glass channel, holy cow!  anyhoo, here is a pic
with the glass ready to rock and roll.  I taped the electrical wire and pulling rope onto the inside of the glass - PRO TIP 8)
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#6
Next, you need to tackle the channel on the car where the unit will sit.  I was again very lucky in that the "putty" they used at the  factory was still quite pliable so if came off easy.  I used a plastic scraper, and my trusty 3M Adhesive Remover, and micro
fibre cloth, came off like a dream.  Once again 3M saves the day ;D 
Some pics of the before and after, make sure you surgically clean the channel, no going back afterwards:


Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

Now comes time for the 3M Bedding and Glazing compound, and keep the beer chilled for when you're done ;)



Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

I used 2 tubes, and ran 2 x 1/4 inch wide beads all around to entirely cover the channel.  I had some left over on the 2nd tube but don't be shy in the application, any "ooze out" can be cleaned
afterwards again with the 3M Adhesive cleaner (can you tell I really like 3M 8)):



Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

You will see some Miracle Paint touch ups here and there, some surface rust had to be dealt with, but overall there was almost no rust in the channel, a great relief.
You might notice however that the trim clips are badly rusted (more on this later)
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#10
Now comes another "nerves of steel" moment.  You need to now drop in the glass into the channel, and essentially you reverse the process of taking it out.
Make sure you have the blanket in place on the trunk, curved side down.  Then slide the unit on the blanket right to the edge of the channel.  Then in one motion,
pivot the unit by resting the bottom into the channel then making the arc slowly and evenly onto the channel.  I was able to reach into the car (long arms 8)) and catch the
unit to gently bring it onto the channel.  Again, if you have helper one will be inside, and one outside of course.
I used these suction cups afterwards to slowly move the glass into place.  To be honest I was very nervous to use these as they grab the glass very tightly, and I was worried that the
differential "grabbing" might cause a crack.  So "use it, don't use it", up to you.  Worked for me:



Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#11
As you can see, I had the rope "open" at the bottom, and was planning on pulling it in from the bottom to the top.  But I think because of the car being on the incline
it pushed more on the top of the car than the bottom, thus it had more pressure on the top than the bottom, so in effect it was pulling away at the bottom, so I had to "change gears" and pull the rope from the top.  Other members actually advocate to start from the top, and
I can vouch that it made the pulling in of the seal a breeze.  So I had to fish out the rope from the top with a pick very carefully, then proceeded to slowly pull and guide the seal onto the
pinch weld.  Slow and steady, and alternate in pulling the LHS and RHS so you end in the middle bottom.  Once you have the rope clear, you now have to tape the electrical cord back down
and reconnect the ground and live connection on the LHS and RHS.  Also you need to make sure the dome light electrical line is taped down properly before you put any of the trim back.
Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#12
Again here I followed fellow Saffa's advice (Ryan a.k.a "s class") and I did not put sealant on the outside of the glass.  I really do think this is overkill, and to my eye would
be very messy, and hard to do, in that the seal is very tight against the glass, so in my opinion it is doubtful that you can get a good squirt of sealant into this tight space.  But of course many folks
do this step, so do as you please.
Seal fully installed:



Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#13
Earlier I mentioned that I had some badly rusted trim clips,  and this became apparent when I tried to put the trim back.  At crucial points, like the bottom RH corner,
I am missing a clip, in that the "teeth" had broken off due to rust, so the trim is not being grabbed at this point.  Thus overall the trim is not sitting as I would like, but honestly I think the only
way to fix this would be to replace all the clips, and I am not taking the glass out again to fix this, HELL NO :o.  So I need to get creative to get the trim to sit properly.  But overall, it came out
nice I think:



Daniel
1977 450 SEL 6.9 - Astralsilber

daantjie

#14
Now put all the interior trim back, and go and have that ice cold beer ;)
Daniel
1977 450 SEL 6.9 - Astralsilber