Can The Rear Defogger Grid Wires Be Re-soldered back on (123)?
 

this is normal - it should have been rope style in the rubber seal, correct? Check Chads rear window replacement thread in the body forum.

If you have the cash, try xylene or at least IPA (isopropyl).. which surface are you worried about cleaning?

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When the PO installed the apparently used rear window glass it cam without the Defogger Grid wires attached. Can these wires be re-soldered to the grid? (Has anyone done this before?)

you need a base for the solder to stick to if you are talking about the connection to the grid on the glass. I was inder the impression there were clips there.. no?

I hate rust!
http://i242.photobucket.com/albums/f...esel911/zw.jpg
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You're worried about grid wires? :eek:

Nothing wrong with looking ahead I guess.

I am just worried about that purple Tribble escaping into the wild.... aren't they supposed to be on leashes ?

I did not know what a Tribble was - No, I am not a trekkie.

Yes, a rear window defogger I view as a safety feature that I would rather not do without. I noticed when I was removing the window there are some vents back there. My heater works but not hot defoggin air comes out of those vents.

The (-) and (+) copper strips (that I called wires) are there but were I guess left over from the origional window and not attached to the window.
The replacement window that I think was a used one also has no copper strips or wires attached. However, the grid lines (exposed on the inner exterior of the window) all seem OK when I probed with my Ohm Meter.

One Member E-mailed me and said there is a conductive Epoxy. I will do an internet search for that as it should work.
I also saw some stuff in a syringe a long time ago "Liquid Circuit Board" that you could make a circuit board with. Unfortunately I do not remember where I saw it; Radio Shack does not sell it either.

While you've got the rear window out, now would be a great time to clean your fuel gauge sender, replace the rear speakers, and possibly re-carpet the back.

How hard was it to remove the rear window? I need to replace the gasket on mine and fix rust around it as you do. I would pay to have a competent glass company reinstall it, but would like to take it out at home so I can fix the rust spots.

Can you post pictures of these vents and copper strips that your talking about?




BTW- I think you mentioned this before when you were rebuilding your rusty lower control arm.... Your car is not an original California car right? It seems to come from the east coast with all that rust!

Here's the thread where Chad describes his rust repairs.

http://www.peachparts.com/shopforum/bodywork-repair-paint-tools-tips-tricks/202295-remove-window-seals-repair-rust.html

He did a great job and his documentation of it was also very good. I hope that helps.

Did this on My W115.
 

I would assume, never having taken out the rear screen on a W123, that the copper strips running down each side of the glass are at least similar to the W115. You need to clean these strips well with Deoxit or the like so the solder will bond well: both those on the glass and the ones attached to the lead wires. Since these strips tuck up under the rubber gasket on the inside, I soldered them together then gently filed any stray solder lumps as smooth as possible with a finger nail file to get as good a mechanical seal as possible. Make sure all parts involved are hot enough to make the solder run rather than clump up. You'll see what I mean once you get into it. Use a pen torch instead of an iron if available. I can't see doing it properly without one really. You want the copper contacts right up against eachother rather than connected at intervals with a spot of solder. I tried generic ACE solder first and it did not work so well. I had some high silver content solder I used in a home speaker crossover project a while back and it did the trick nicely. partsexpress.com has what you need on the cheap.

Works like a charm now. A PO had replaced the rear glass at some point and just tucked the leads under the parcel shelf. No end to the shortcuts some folks will take to save a buck or three at the most.

Sam

There's a kit for this
 

Permatex makes a repair kit for rear window defoggers. There's an article about using it here- http://www.rd.com/familyhandyman/content/55830/

I don't think that kit will work. That is for the type of grid that is painted onto the surface of the glass, with grid lines that are about 1/32" wide.

I don't know about the other W123 models, but on my 300CD the lines are REALLY thin and there are a LOT of them - about 1/4" apart running top to bottom instead of side to side. I haven't looked closely enough to be sure, but it looks as if they might actually be hair-thin wires imbedded in the glass.

If that's the case, the permatex kit wouldn't work. If I'm wrong, I'm sure others will chime in and correct me...

I think the W123 sedans have more conventional wires, my W126 has the small wires laminated between the layers of glass. You can hardly see them!

-Jason

The W123 has conventional wires, the Coupe isn`t Conventional.

The Coupe rear window is like the W126 with the wires laminated in the glass.

Charlie