Hiya MacDuff,

What's with all the Nazi infestation? Are you in the Kremlin?
Maybe driving around Google or Kroeger's corporate HQ (to name just two)?

The only experience I have with side view mirrors is having one get croaked
and replacing with a JY unit. Don't go to the dealer unless price is no concern.

Now I see that there's special adhesive sheets and strips and circles etc
to bond the backing plate to the mirror. Have you considered them?

https://www.amazon.com/Replacement-Mirror-Glass-ADHESIVE-Driver/dp/B00WXGPMFC

They sell curved and straight replacement mirrors with and without the adhesive sheet and some supply a silicone adhesive.

It's odd how Murphy works. Because you mentioned wiggly side view mirrors,
I noticed my driver side view starting to do the shimmy on the highway racetrack this weekend.
Maybe my mirror is getting ready to fall off in sympathy with yours?

Sorry to hear about Dia-beet-us over there, cut down on the beets.

Cheers, Bill

PS: Great Google popup ads here now (a public service): "Get 1-year CD @ 12% interest". That sounds good, but I'm waiting for a chance to pick up the Brooklyn bridge cheap.

Bill, I've used marine grade GE silicone sealant for mirror glass twice now and with no problems for over 2 years. After talking to mechanics, we decided the best pattern to prevent air bubbles and moisture being trapped was an upside down W inside an upside down U. Not too thin a bead, not too thick (definitely not too thick if it's a heated mirror as in the 900s). I put a small block of 2x4 against the glass and wrapped it tight as I could with multiple bungees for an overnight cure.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Hi Dave,

OK on the silicone. Do you have any photo's?

I see different methods that work and they must have some trade-off of performance, price, and ease of use.
I talked to my local pal this AM and he used some 3M stuff before with success.
Dunno what the auto glass places like to use.

What do you make of my mirror shaking at high speed? It's never done that before.
Does that mean that it's starting to fail? Does it come apart to inspect or do
I wait for it to fall out?

Cheers, Bill

A vibrating mirror image is the classic warning sign that the mirror glass is letting go from the backing plate. You're probably not far from the point, if not already there, where there will only be a hinge of bond left, seemingly often at the top, where you can lift the glass up a bit on the opposite side. Get some packing tape on before it completely lets go and smashes on the ground, until you're ready to tackle the job. When working the mirror off, use a sharp thin blade up under the edge of the glass working carefully back and forth. A sharpened, long bladed, flexible kitchen carving knife was my weapon of choice. The only tricky bit is being careful not to dig into the silvering, so dig into the plate side in areas where it doesn't want to separate. In the 900s it's like some kind of rubber film bond done under high heat. I imagine the later 240s are similar. It may come off a bit unevenly in places depending on how good you are. Just glue it up and stick it back down and you'll be good to go, maybe first using an isopropanol wipe to remove any dirt and oils. Acetone might also be useful to help roughen up the bonding surfaces, which I think I likely used.

Here's the GE Marine Grade clear silicone sealant I used. Cost about $11 and in stock at a number of local hardware stores in Canada, but for some reason I'm not seeing it available in the USA, not even on Amazon, so you may have to find something similar. Marine Grade often means it includes UV protection, which is unimportant behind a silvered mirror. Flexibility to cope with expansion would be a necessary attribute, so definitely clear over anything with white pigment in it, also not latex water cleanup.


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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

both mirrors on my porsche 944 fell off before I bought it. I assume they hit the ground and smashed. behind its a rubber backing. I got replacement mirrors from rockauto and they came with a thick double-stick tape which I dont really trust.. I thought I might use both, that and maybe the silicone, beside each other? not sure what sticks to rubber. im not sure if those are heated. I have some power mirrors from a 89 740 ( I took a whole car apart for spare parts) if someone needs them.

That 1991 240 mirror is translucent. While mirrored, you can see through it.

The lettering for the 'things are larger than they appear" is on the flexi plati9c backing plate. Or left on when it nearly fell off the first time.

You'll want a UV resist or proof adhesive something.

Thank you folks, kindly. Still fingering through your idea'rs!

Moar eeeemojeeeeeez, pleaze!!!!
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