windshield do it yourself - PeachParts Mercedes-Benz Forum

greendream · #1 09-25-2009, 07:39 AM

I had a large tree branch hit the windshield of my 1979 300SD this week. The shops in town willing to do the replacement are pretty expensive so I thought i'd research doing it myself. I found a used replacement on the adsit website and the seal is also available. Has anyone on the is forum done this job? Any advice on installation to make sure it seals properly and doesn't leak?

TIA

loepke72 · #2 09-25-2009, 09:31 AM

I just did this on my W116 last week. I have only one leak in the lower right corner to contend with, found after a heavy storm. The seal is not fitting tightly enough around the windshield in that area. Haven't done anything with it yet.

Do yourself a favor, get the windshield seal from the MB dealer. There seems to be a consensus regarding that. The old windshield should just push out from the inside of the car. Assemble the new seal to the windshield first, then install the aluminum trim pieces. Next, install a rope into the channel in the seal that will go over the lip on the car body. Make sure the sealing areas on the car are clean of rust, old rubber, sealant, etc. The channel in the seal where you will put the rope is not real obvious at first glance. It's hard to describe it in words here. Use some kind of lubricant that will not damage the rubber on the channel. I found out the hard way by not lubing it. I had to spray silicone lube on the seal when it was half installed. Now set the assembly on the windshield opening on the car, making sure to get it aligned properly. It is impossible to realign once the seal is started on the metal lip. Start the seal on the lip by hand, then pull out the rope. You will have to push down on the seal as it is rolled over into place. Oh, I forgot, make sure the free ends of the rope are on the bottom of the assembly. When the bottom of the seal is rolled over, push down on the top of the windshield from outside to get it seated as far down as it will go. A few taps with the palm of your hand should work. Then continue pulling out the rope and working the seal into place. The corners are tricky; sometimes pushing in the seal from the outside with a blunt tool will help. After getting the inside lip of the seal in place, make sure the outside lips (the ones that are on the outer edge of the seal) are not rolled under the seal or windshield trim pieces. Lightly tap the outside of the seal with your hand to get it seated. After that, go ahead and check for leaks and repair as needed. I did not use any kind of sealant on the seal, but I'm sure it could be applied to the opening in the car before installation of the windshield assembly.

thorsen · #3 09-25-2009, 09:46 AM

My W116 is in dire need of new front and rear seals. After the windshield debacle with my W114, I am going to attempt to do it myself this time. It sounds easy enough and I understand the concept so I have high hopes. It's only glass after all.

I'm another believer in using the dealer seals. I got burned by buying aftermarket.

greendream · #4 09-25-2009, 09:59 AM

Quote:

Originally Posted by loepke72

I just did this on my W116 last week. I have only one leak in the lower right corner to contend with, found after a heavy storm. The seal is not fitting tightly enough around the windshield in that area. Haven't done anything with it yet.

Do yourself a favor, get the windshield seal from the MB dealer. There seems to be a consensus regarding that. The old windshield should just push out from the inside of the car. Assemble the new seal to the windshield first, then install the aluminum trim pieces. Next, install a rope into the channel in the seal that will go over the lip on the car body. Make sure the sealing areas on the car are clean of rust, old rubber, sealant, etc. The channel in the seal where you will put the rope is not real obvious at first glance. It's hard to describe it in words here. Use some kind of lubricant that will not damage the rubber on the channel. I found out the hard way by not lubing it. I had to spray silicone lube on the seal when it was half installed. Now set the assembly on the windshield opening on the car, making sure to get it aligned properly. It is impossible to realign once the seal is started on the metal lip. Start the seal on the lip by hand, then pull out the rope. You will have to push down on the seal as it is rolled over into place. Oh, I forgot, make sure the free ends of the rope are on the bottom of the assembly. When the bottom of the seal is rolled over, push down on the top of the windshield from outside to get it seated as far down as it will go. A few taps with the palm of your hand should work. Then continue pulling out the rope and working the seal into place. The corners are tricky; sometimes pushing in the seal from the outside with a blunt tool will help. After getting the inside lip of the seal in place, make sure the outside lips (the ones that are on the outer edge of the seal) are not rolled under the seal or windshield trim pieces. Lightly tap the outside of the seal with your hand to get it seated. After that, go ahead and check for leaks and repair as needed. I did not use any kind of sealant on the seal, but I'm sure it could be applied to the opening in the car before installation of the windshield assembly.

thanks for this reply. would this job go easier with an assistant?

Mike D · #5 09-25-2009, 10:13 AM

A few more tips. Keep a cup of ice and a wet cloth near by. It comes in handy about the third time you punch yourself in the face!

Keep your hands clean and dry! Don't get any lube on the end of the cord you are pulling. I find it useful to knot the cord as it comes out. It gives you a more convenient gripping area. Double loop the cord because once you pull it past a tight spot, you aint getting it back in the seal if the lip doesn't pull through without taking the whole shebang back out.

rs899 · #6 09-25-2009, 10:52 AM

Mike-

I agree with the ice

.

I use a long piece of coated wire that works well and keep spraying everything down with Windex to keep it slick. I had a hell of a time with the W116 front aftermarket seals (way way too loose), so OEM is the only way to go on those. I have never had a problem on a W123 and the W116 rear Meyle seal worked OK too.

It is very important to start with the glass exactly in the center. If it is off center, by the time you get to the sides you will not be able to pull the rubber on the tight side. Once you get about half the bottom set you may be able to carefully slide and re-center the glass but don't stess it, or else...

You definitely need an assistant, maybe 2.

Rick

loepke72 · #7 09-25-2009, 11:32 AM

I'd recommend the assistant to keep the glass in place when installing, even though I did it "flying solo". I had a couple of false starts due to the glass getting out of alignment. The glass was slightly off center finally, but not enough to stop the seal from installing properly. It will take practice; I would probably have less trouble doing the next one now.

79Mercy · #8 09-25-2009, 09:22 PM

Wish me luck im replacing the windshield on my W115 tomorrow or the next day, i already have the old one out. MB sells a sealant which you should use between the the body of the car and the seal, if you can't get the Mb stuff black silicone should just as good.

Anyone know what type and size rope is best to use?

Mike D · #9 09-26-2009, 06:30 AM

Not silicone. Butyl rubber. The RTV silicone actually promotes rust.

I use a heavy braided twine. The waxy stuff works pretty good.

rs899 · #10 09-26-2009, 07:20 AM

Think slick. Clothesline might work OK. I use a piece of oil resistant wire that is thinner than clothesline, maybe its 10 ga.

Silicone is bad between the pinchweld and the rubber, but I run a bead of that thin clear stuff between the glass and rubber (mostly at the bottom). Butyl rubber works but I guess is very permanent. I use 3M Bedding and Glazing Compound that you can get in auto paint stores.

Good luck- the first one is always the hardest...

Rick

79Mercy · #11 09-26-2009, 07:18 PM

OK i'll get some Butyl rubber. I goes between the body of the car and the inner part of the seal correct?

Bill Adkins · #12 09-28-2009, 09:54 AM

Those glass pieces were origonaly installed with a lubricant, not a sealant. If the glass is sealed you will never remove it again in one piece. I installed many, years ago using #12 wire and silicone lubricant. As for silicone causing rust I hadn't heard that before.
Bill

eclipse_22 · #13 10-07-2009, 02:24 AM

So my car is going into paint but need to REMOVE front and rear windows. How do I do that without damaging the window and keeping it whole. Do i just take a razor and start hacking away around the windshield and use some fishing line and across?

rs899 · #14 10-07-2009, 06:43 AM

Eclipse-

Not sure what your car is but on a W115 or W123 I use one of those disposable box cutters with the long snap-away blades and cut the glass out first, then cut the trim out.

230/8 · #15 10-07-2009, 12:53 PM

Why spend extra for a factory rubber seal and then wrap it around a used sand-pitted windshield? I'd get a fresh piece of glass from the dealer and do the job once. And, I'd never buy from a company with a no return, no exchange, no exceptions, you're-on-your-own policy. Personal opinion...