S4 Fog lights
#1
Vegas, Baby!
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S4 Fog lights
Is there a way to get the glass lenses out of the plastic housings with out breaking the lenses, or the housings? I have a spare fog light assembly with a good lens, and one with a cracked lens. The plastic frames need to be swapped.
Any ideas, are the lenses glued in?
Any ideas, are the lenses glued in?
#2
Chronic Tool Dropper
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"Other Cars" use an adhesive that softens at around 300F. If you don't get a good answer you might try heating the assembly in the oven and see what comes loose. Take all the little plastic arms and other sensitive pieces out, maybe the reflectors too.
#3
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I have a set out on a bench. I'll take a look and report back.
#4
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Roger sells just replacement lenses so they are definitely removable. IIRC you heat them to around 215 or 220 and can then remove the lenses.
You might give Roger a call as I'm sure he has the instructions for his replacement lenses.
You might give Roger a call as I'm sure he has the instructions for his replacement lenses.
#5
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Yup. They're glued on.
#6
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Did a quick experiment with a foglight that had taken a rock hit:
Started with 15 minutes at 225oF, then took a big flatblade screwdriver and started prying. The adhesive was a bit more gooey but I was cracking off bits of glass without any give.
Back into the oven at 250 for 15 minutes. The adhesive could be scraped but it was still holding.
Back into the oven, 10 minutes at 300. Softened enough to separate.
I suspect that 325 would be ok, the plastic housing was still fine at 300.
Started with 15 minutes at 225oF, then took a big flatblade screwdriver and started prying. The adhesive was a bit more gooey but I was cracking off bits of glass without any give.
Back into the oven at 250 for 15 minutes. The adhesive could be scraped but it was still holding.
Back into the oven, 10 minutes at 300. Softened enough to separate.
I suspect that 325 would be ok, the plastic housing was still fine at 300.
#7
Vegas, Baby!
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Thanks Rob, you're the master!
I'll do it tomorrow!
I'll do it tomorrow!
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#10
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The adhesive is kind of all-or nothing, some stayed with the housing but some went completely with the lens.
Begs the question of what the adhesive _is_....
Begs the question of what the adhesive _is_....
#11
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Clear RTV works fine for the install of the new lens.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
#12
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The channel in the foglight housing for the adhesive is 6 mm- I think that this 7.5 mm Morimoto butyl glue looks interesting, and is available in gray. Roll out to desired thickness, install in the channel, heat at 265 for 7 minutes, press together.
https://www.theretrofitsource.com/mo...lue-51567.html
https://www.theretrofitsource.com/mo...lue-51567.html
#13
Be absolutely sure you've heated the glass and housing entirely, and DON'T PRY on it... I've chipped the glass lens on previous vehicle's fog lights because I was impatient and thought I could get it loose enough to overcome the adhesive using a pry tool and sharp blade.
The nice thing about the 928 fog lights is that the reflectors and other sensitive bits can be removed from the back so you're really only baking the glass and housing. I've tried using mineral spirits on the adhesive and it's really slow going and doesn't work well. I think that using an aggressive adhesive remover would make a reseal with RTV not work as well as it could if the remover was left behind in any way (like being saturated into the original adhesive and not completely wiped away).
The nice thing about the 928 fog lights is that the reflectors and other sensitive bits can be removed from the back so you're really only baking the glass and housing. I've tried using mineral spirits on the adhesive and it's really slow going and doesn't work well. I think that using an aggressive adhesive remover would make a reseal with RTV not work as well as it could if the remover was left behind in any way (like being saturated into the original adhesive and not completely wiped away).
#14
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Started with 15 minutes at 225oF, then took a big flatblade screwdriver and started prying. The adhesive was a bit more gooey but I was cracking off bits of glass without any give.
Back into the oven at 250 for 15 minutes. The adhesive could be scraped but it was still holding.
Back into the oven, 10 minutes at 300. Softened enough to separate.
I suspect that 325 would be ok, the plastic housing was still fine at 300.
Back into the oven at 250 for 15 minutes. The adhesive could be scraped but it was still holding.
Back into the oven, 10 minutes at 300. Softened enough to separate.
I suspect that 325 would be ok, the plastic housing was still fine at 300.
#15
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Meh, I spent the whole freaking weekend R&R'ing the convertible top canvas on her CLK, I earned some buytl-rubber-adhesive-smell-on-her-cutting-board points.
You think 928s are Germanically maniacally complicated? Pfft.
You think 928s are Germanically maniacally complicated? Pfft.