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Rear window seal replacement

Started by daantjie, 11 June 2017, 03:36 PM

daantjie

Hi guys

Washed the 6.9 yesterday.  She shined up good but I just again realized how shot my front and rear window seals are :o
I know the front seal has a lot of shenanigans involved, but how about the rear?  Anybody care to share some words of wisdom?
Looking for questions to:
1) Is it a 1 man job?
2) How easy is it to break the glass - I know this is relative but I really don't want to break the glass of course as I've read that new rear glass quality is crap
3) What brand?  I know that URO is garbage but some folks report the fit is actually not bad on the URO front seal?

Cheers
Daniel
1977 450 SEL 6.9 - Astralsilber

Zaxxon

Sorry, I don't have any advice for you at this point, but I will be following this thread closely, since my rear window seal is basically crumbling bits and pieces. I have a new seal for the front already here that needs it too, but the rear even more so!

--Zax
---
Mercedes: '99 CL500, '86 500SEC, '96 SL500, '06 R500, '02 ML320, '78 450SEL
Porsche: '80 928S 5-Speed, '86.5 928S RogerBox '86.5 928S 5-Speed, '83 944
Others: '84 Callaway Alfa Romeo GTV6, '83 Tiara, '87 FZ

robertd

Hi Daniel

since I have been involved with W116's over the last 15 years I have stripped 4 complete cars.
I have found the best way to remove the rear screen without damage is to first cut the old rubber seal all the way round with a sharp knife (box cutter).
then from the inside (better with two people) position yourself on the back seat and push the glass gently and evenly with your feet!

might look funny but works well, no stress, no damage.

cheers

take some pictures for the album.
116   1978 450SEL 6.9 #  4848
116   1979 450SEL  6.9 # 5884
116   1979 450SEL  6.9 # 6225  SOLD
116   1978 450SEL  6.9 # 5128  SOLD
116   1979 450SEL  6.9 # 5884  SOLD
116   1974 450SEL  DJet

daantjie

Thanks guys, I think it'll be some time before I tackle this monster.  In the meantime here is a link I found online which shows a somewhat generic approach between models:

http://www.peachparts.com/shopforum/body-repair/238275-rear-windshield-seal-w116-123-126-a.html
Daniel
1977 450 SEL 6.9 - Astralsilber

s class

Ive done a couple of 116 rear screen seals.  Its a lot easier than the front due to not having to fit the garnish mouldngs into the rubber. 

I agree about cutting the old seal out. 

I've used the URO rear seals with no issues, held up now for nearly 10 years, though admittedly my car doesn't see much sun.

I would not attempt this without an assistant. 


[color=blue]'76 6.9 Euro[/color], [color=red]'78 6.9 AMG[/color], '80 280SE, [color=brown]'74 350SE[/color], [color=black]'82 500SEL euro full hydro, '83 500SEL euro full hydro [/color], '81 500SL

ptashek

According to my restorer, the rear seal is a breeze to put in with two people doing the job. Zero drama like with the front, which is an absolute ..... to put in.
Taking out the rear - I support the cutting seal out first approach. I did that on my 350 without any help, and the glass came out willingly with a gentle but steady push.

I have a genuine MB seal in my 450. I had an URO one, but changed my mind at the last minute and went OEM.
It fits well (unlike the current OEM front, which we had to scrap and source a NOS one). Looking at it, I'm near certain it's made by URO though - or if not, the URO one is a really good copy.
1993 "Pearl Blue" W124 280TE
1988 "Arctic White" W124 200T
1979 "Icon Gold" W116 450SE

daantjie

#6
Thanks guys

So just to confirm, you take the chrome strip out BEFORE you cut the seal out and push it out, then you apply the seal on the glass, refit with sealant, and then you put the chrome strip back AFTER the unit has been bedded in?  Seems to me as if you will be fighting the seal to get the strip back into the rubber channel after it has been compressed into the body, no :o?  Sorry I am being a bit slow on the uptake here ;D

Also, I see clips on the steel frame of the body in some pics, what is the function here, does the seal slip into these clips?

Cheers
Daniel
1977 450 SEL 6.9 - Astralsilber

UTn_boy

The clips you're seeing in the pictures are the clips that hold the aluminum trim to the car, as they are not pushed into the rubber seal.  The rear glass seal has no trip that pushes into it.  So yes, you remove all of the aluminum trim before you remove the glass, and it's the last thing you put on on the outside. 

Bear in mind that you'll have to remove the back seat, parcel shelf, "C" pillar panels, interior roof rail panels at the rear, and the ones that house the roof rail grab handles in order for the new seal to lay over the pinch weld as you rope it in, and also to gain access to the wire connections that re for the electric part of the rear glass. Also, if your seal is original, it'll have glazing putty in between it and the chassis, and will likely be rock hard.  This is why is best to but the glass out of the rubber, and then remove the rubber seal.  After the seal is removed, you'll have to literally get a slotted screw driver (a dull one) and "chip" out the old glazing putty inch by inch.  Wear safety glasses when you do this, as the pieces will fly off in every direction. After that is all removed, touch up the entire perimeter of the glass opening with paint to treat any bare metal showing from chipping away the glazing putty.  Also, this would be when you treat/take care of any rust that's under the seal. 

Save your old lower corner pieces of the old seal for reference as to where to cut holes in the new seal for the heated glass wires.  Make sure that the grommets the wires go through in the chassis are serviceable, too. 

For sealant, do NOT use Butyl on the front or rear glass.  The correct sealant is still available from Mercedes.  Buy two tubes of it. It's not that expensive. Part number 001-989-31-20.  The tubes of sealant fit in any regular caulking gun.  You'll put sealant around the glass opening on the car itself first.  Use a lot.....to the point that you think it's too much.  (essentially, when you rope the glass in, you want there to be excess that squishes out)  After the glass is roped in, you'll insert the plastic nozzle of the tube of sealant in between the glass and the seal.  Again, allow for excess to the point of it squishing out.  You don't have to do the top of the glass, but you can if you wish.  Afterward, let everything set up over night, and then come back with a knife to cut the excess even with the seal/glass, and remove the excess.

It's not a cakewalk type of job, as it's extremely time consuming, but not all that difficult. 
1966 250se coupe`,black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3,papyrus white/dark red leather
1975 450se, pine green metallic/green leather
1973 300sel 4.5,silver blue metallic/blue leather
1979 450sel 516 red/bamboo

daantjie

Quote from: UTn_boy on 12 June 2017, 11:35 AM
The clips you're seeing in the pictures are the clips that hold the aluminum trim to the car, as they are not pushed into the rubber seal.  The rear glass seal has no trip that pushes into it.  So yes, you remove all of the aluminum trim before you remove the glass, and it's the last thing you put on on the outside. 

Bear in mind that you'll have to remove the back seat, parcel shelf, "C" pillar panels, interior roof rail panels at the rear, and the ones that house the roof rail grab handles in order for the new seal to lay over the pinch weld as you rope it in, and also to gain access to the wire connections that re for the electric part of the rear glass. Also, if your seal is original, it'll have glazing putty in between it and the chassis, and will likely be rock hard.  This is why is best to but the glass out of the rubber, and then remove the rubber seal.  After the seal is removed, you'll have to literally get a slotted screw driver (a dull one) and "chip" out the old glazing putty inch by inch.  Wear safety glasses when you do this, as the pieces will fly off in every direction. After that is all removed, touch up the entire perimeter of the glass opening with paint to treat any bare metal showing from chipping away the glazing putty.  Also, this would be when you treat/take care of any rust that's under the seal. 

Save your old lower corner pieces of the old seal for reference as to where to cut holes in the new seal for the heated glass wires.  Make sure that the grommets the wires go through in the chassis are serviceable, too. 

For sealant, do NOT use Butyl on the front or rear glass.  The correct sealant is still available from Mercedes.  Buy two tubes of it. It's not that expensive. Part number 001-989-31-20.  The tubes of sealant fit in any regular caulking gun.  You'll put sealant around the glass opening on the car itself first.  Use a lot.....to the point that you think it's too much.  (essentially, when you rope the glass in, you want there to be excess that squishes out)  After the glass is roped in, you'll insert the plastic nozzle of the tube of sealant in between the glass and the seal.  Again, allow for excess to the point of it squishing out.  You don't have to do the top of the glass, but you can if you wish.  Afterward, let everything set up over night, and then come back with a knife to cut the excess even with the seal/glass, and remove the excess.

It's not a cakewalk type of job, as it's extremely time consuming, but not all that difficult.

Thanks Aaron, as always for the very thorough and detailed response ;D

Indeed this does sound like an all weekender type job.  I always spend a lot of time cleaning and prepping parts and surfaces when I work, so I would rather really take my time and clean to the point of surgical cleanliness most of the time than wonder afterwards why parts won't fit properly.  Then at least that is one thing I can eliminate ;D

This stuff seems to be also very good to use:

http://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Auto-Bedding-and-Glazing-Compound?N=5002385+8743654+3293194048&rt=rud

I am still paranoid about breaking the glass but I guess you need to just say a prayer to the Benz gods and take it slow and then let the chips (hopefully not glass shards) fall where they may 8)
Daniel
1977 450 SEL 6.9 - Astralsilber

Squiggle Dog

For what it's worth, I haven't had any trouble removing windshields by just using plastic prybars and slowly sliding the inner lip of the seal under the pinch weld until it's completely on the other side and then just lifting out the glass with the seal intact--unless someone used a hardening sealant which essentially glues it in place. Be careful you don't cut the defroster wire.
Stop paying for animal cruelty and slaughter. Go vegan! [url="https://challenge22.com/"]https://challenge22.com/[/url]

1967 W110 Universal Wagon, Euro, Turbo Diesel, Tail Fins, 4 Speed Manual Column Shift, A/C
1980 W116 300SD Turbo Diesel, DB479 Walnut Brown, Sunroof, Heated Seats, 350,000+

daantjie

Guys need some more guidance on the sealant application; sorry if I'm being a bit thick here ;D
So you apply the sealant liberally into the channel where the seal will sit and also covering the pinch weld with sealant before you introduce the glass with new rubber seal to the cavity?
Then after you rope in the seal on the inside you then proceed to the outside of the car and apply the sealant between rubber and glass?
This all sounds very messy, how the heck will you clean off all the sealant that will surely end up everywhere? Also do you let the excess sit exposed then scrape/clean after the 24hr bedding in period?
Thanks for schooling the slow Saffa 8)
Daniel
1977 450 SEL 6.9 - Astralsilber

Squiggle Dog

From what I have seen, the sealant goes in after the seal is installed in the body to avoid messes from the rope sliding out, though I think that the channel where the glass rests can get sealant first and then the excess can be wiped clean after installation. It takes some finagling to lift up the seal and get the caulking tip underneath for application. It should be done in warm weather or with the sealant tube preheated so that it flows well.
Stop paying for animal cruelty and slaughter. Go vegan! [url="https://challenge22.com/"]https://challenge22.com/[/url]

1967 W110 Universal Wagon, Euro, Turbo Diesel, Tail Fins, 4 Speed Manual Column Shift, A/C
1980 W116 300SD Turbo Diesel, DB479 Walnut Brown, Sunroof, Heated Seats, 350,000+

daantjie

#12
Hi guys

Well, I am having an ice cold Alexander Keith's IPA (the pride of Nova Scotia BTW 8)) and in a way I am congratulating myself for a job 90% well done.

Yes, I attempted this by myself...Was it easy, NO :o!  But, a little South African stubbornness goes a looooong way, and she's IN! ;D  No breaks or cracks either (so far) so I am helluva chuffed with myself.

But...For the life of me I cannot get the effing chrome trim back.  Also I am bushed so maybe my brain and hands are just tired, so I could REALLY use some sage advice on any tips on getting the trim back.

I can get the top 2 parts back with no drama, but the bottom curved piece keeps popping out on me, ugh so frustrating...

I will make a separate post on my process, also with pics if I can upload them.

Cheers
Daniel
1977 450 SEL 6.9 - Astralsilber

Zaxxon

Cheers! Enjoy!

Congratulations on the job (almost) done. Can't give you any advice, since I still have to do that job myself, but I am certainly looking forward to your post!!!


--Zax
---
Mercedes: '99 CL500, '86 500SEC, '96 SL500, '06 R500, '02 ML320, '78 450SEL
Porsche: '80 928S 5-Speed, '86.5 928S RogerBox '86.5 928S 5-Speed, '83 944
Others: '84 Callaway Alfa Romeo GTV6, '83 Tiara, '87 FZ

karmann_20v

Wow, so you've (almost) done it! Happy to hear, I am sure somebody here will offer sound advise on the trim - the 115 guy in the vid I sent you could use some too LOL.