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87 560SL Third brake light "turd" disassembled

23K views 49 replies 14 participants last post by  donfenn 
#1 ·
A recent poster told us about how his third brake light housing had crumbled. Since I was taking a few days to give my 560SL a good cleaning (it's been up to 99 here for a few days) and decided to take the turd off the lid and fix some cracks that I'd found.

Here's what that looks like disassembled:

Scale model


It's of astonishingly chintzy construction. Note how the lower corner has completely broken off, as well as two of the screw holes on the inner reflector part.

The rubber gasket, in comparison, is notably more substantial, roughly 5-6mm thick. (Left upper corner.) It's as though they farmed out the job to two different companies, with the plastic housing made in a hurry. I suppose it's better than the other way around. A leaky gasket at this spot would make for a nightmare of rust inside the trunk.
 
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#4 ·
Just out of curiosity, is the smaller 1988-89 3rd brake light housing also made of plastic?

The whole thing reeks of last minute slap-it-together work. Did they really expect that such a hideous design was acceptable on a car that at the time sold for some $60,000? It's not unlike an otherwise beautiful model having a huge wart on her nose. Maybe the typical customer in 1986-87 was doing too much coke to notice it?

I'm going to try to patch mine up as best possible. The cracks are not that visible.
Yes, I know it's possible to fill in the holes and paint it, but that's way down on my list of priorities right now.
 
#7 ·
Well, I suppose it could be worse. Some 80s era Porsches had this mounted on the back.

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Looks like the designer had fallen asleep watching the 1953 version of "War of the Worlds" the night before he sat down at his drawing table.
ET, phone home.
I surrender. :surrender::surrender: That is worse than the Mercedes turd.
 
#11 ·
That looks like the type they adopted for the 1988-89 560SL:

Land vehicle Vehicle Car Motor vehicle Convertible


Not as obtrusive or clunky-looking as the 86-87 part.

It's be nice if it would fit as a replacement for the "turd," but it doesn't appear wide enough to cover the additional two holes that the earlier one has, you'd have to use some filler and paint to make that work.
 
#12 · (Edited)
You can tell by the burgundy top that I'm not a purist; nevertheless I wanted to propose another solution. When my 'turd' broke, I replaced it with the brakelight from a Jaguar XJS convertible, which I purchased from ebay. It was deep enough, front-to-rear, to span the four original holes in the trunk. It's not as tall as the original so is much more streamlined / less obtrusive, plus it was manufactured by Bosch, so the bloodlines are not completely incompatible.

My car is more of a 'resto-mod' than a restoration, so I understand this may not be suitable for everyone's taste.

For those with a good eye, the paint is Astral Silver, with a matte clearcoat. My hardtop is also burgundy, by the way, a tribute to the two-toned styling of the 113s and some of the earliest of the 107s.
 

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#13 ·
I replaced it with the brakelight from a Jaguar XJS convertible, which I purchased from ebay. It was deep enough, front-to-rear, to span the four original holes in the trunk..
I was searching around for something just like that. Do you recall what year that brake light is from? One salvage place has them listed as for "81-91," and "92-94," but there are no photos.

There aren't any for sale on eBay at the moment, but I'll keep looking.
 
#15 ·
I don't find the "turd" on the trunk that big an issue. In addition, it makes them unique.
It might turn out sometime in the future to be like the 1963 split window Corvette.
In the 1960's, some folks went to the trouble to cut out the "split" in the rear window and replace
the glass with glass from the 1964-1967 Corvette. Turned out to be a big mistake.
Back then that split window was looked upon as not pleasing - like our turd?????
 
#17 ·
Well, until I find another solution, I'm refurbishing the existing light assembly.

Product Plastic Floor Table Flooring
Vehicle Automotive exterior Bumper Floor Flooring


Vehicle Muffler
Food Dessert Chocolate Cuisine


I'm using a variety of methods borrowed from the modeling world.

I've glued in the broken parts and filled in the cracks with two-part epoxy mixed with "Microballoons," a powder added to the epoxy that makes it better for use as a filler. The consistency is not as liquid as plain epoxy but not as thick as epoxy putty, and makes it easier to sand. You can find the stuff in any good hobby shop. It's the white gooey stuff.

I also glued in some plastic card stock (also available at a hobby shop) to reinforce behind the flat areas, and used a trick that model airplane builders use for the curved sections: soak some thick tissue, the kind used for model airplane wings and such, in epoxy. It conforms to the bends and is thin enough so that the lens and gasket will fit properly.

The paint job was pretty bad. It looked as though they didn't let the color coat dry thoroughly before they put on the clear coat. It had a bubbly texture. There were also some deep scratches. After filling the cracks I wet-sanded it with progressively lighter grades of sandpaper: 400, 600, 1000, etc.

I'm going to use this as an opportunity to practice repainting using spray paint from paintscratch.com, before I make any attempt to repaint the scratches, chips and oxidized paint on the car's sheet metal.

I'm also going to replace the incandescent 1156 bulb with an LED bulb from superbrightleds.com, so if I have to seal it up to get it to hold together I won't have to worry about opening it up again.
 
#19 ·
My 1986 560SL doesn't have a 3rd lamp. It was removed and the holes filled in when it was repainted back around 2001 by my brother the PO. Only downside is that the idiot light on the dash that warns of a lamp out is always on. Hasn't been high on my priorities to figure out what to do about it but I wonder if anyone who has removed theirs has come up with a solution (other than just removing the dash bulb) to fix that.
 
#20 ·
Well, the easy way to fix that would be to wire a socket to the existing wiring inside the trunk and put a bulb in it. It'll only go on when you hit the brakes.

I found when rewiring my headlights with relays that the bulb out indicator was on when I put the headlights on. The relay didn't provide enough resistance for the bulb out control unit. So I added to the relay coil circuit a 4 Ohm 100W resistor. That worked, the bulb out indicator now only goes on when a bulb is in fact out.
 
#21 ·
Update:

I've filled in the various cracks, reinforced the stress points, etc.

The "reflector" portion of the assembly is merely painted silver. I was just going to give it fresh coat of silver paint, but when I stopped in at my local auto parts shop, I found this stuff, Chrome Brite Metallic Tape.

Games


It's much more effective than mere silver paint, almost a mirror-like reflection, which should do a better job of getting the output of the LED cluster bulb delivered to the lens.

Using the reflector as a guide, I traced out the top and bottom semi-circles and measured and cut a portion to fit the back, which I then cut and trimmed with a hobby knife until it fit properly. There's a few wrinkles and bubbles, but it's not a big deal because it'll all be sealed up anyways.

Scale model Auto part Vehicle Metal


I've also begun re-painting the housing,using a paintscratch.com spray can of 587 Cabernet Red. In this photo it has a couple of light coats already. Once I've got a thick enough coat of the base color and have let it dry thoroughly, I'll put on a few layers of clearcoat.
 
#22 ·
Another update. I let the base coat dry overnight, then today I sprayed on several light coats of clearcoat. There were a few bubbles that I then sanded out with 2000 grit sandpaper and applied a few more coats of clear.

Auto part Automotive exterior Fender Plastic
Red Praline Dominostein Rectangle Square



Paintscratch.com says to wait three days before using rubbing compound to give the clearcoat a good luster, so I'll have to drive around with this on the lid, we've had some showers the last few days so I want to keep the rain out.

Pink Red Magenta Material property Tints and shades


By the way, that's not duck (or duct) tape, it's gaffer's tape, which you can find online or at a place like Pearl Art Supply. Gaffer's tape does not leave a sticky gooey adhesive residue like duck tape does.
 
#23 ·
Who says you "can't polish a turd?"

"You can't polish a turd." That's a saying attributed to Jerry Lewis when he was editing one of his films. He said it to Stanley Kubrick who was working just down the hall.

I let the thing sit for 3 day for the paint to cure, and then polished it with various grades of polish, then put the thing back together again.

One thing that also shows the turd's cheapness is that the gasket doesn't even go all the way around the lens. It's about 1/2 inch too short. But it's all plastic so you don't need to worry about rust.

Wood Scale model Vehicle Flooring Games


The lens is only held in place by friction with the gasket. After fussing and finagling with it, I found that the only way I could put the thing back together again was to unscrew the weird studs, take the reflector portion back out of the housing, then fit the gasket around the reflector, push on the lens, and then shove both of them into the housing. Keep that in mind if you need to replace the bulb.

Don't lose those four studs, I doubt you'll find anything like them at the hardware store. One end has large threads to screw into the plastic reflector and on the other end a finer thread for the 10mm nuts that hold it to the trunk lid, and there's what looks like a 10mm nut in the middle that is not separate from the stud.

Red Vehicle Material property Car Magenta


Whilst doing so I reopened two small cracks on the lower sides that I'd carefully epoxied and filled, but they aren't that noticeable.

It's better than it was, and I replaced the 1156 bulb with an LED array, which means I shouldn't have to open the thing up again. Of course now my "bulb out" idiot light is on, but I'll deal with it.

Oh, and by the way, Stanley Kubrick thought about it for a moment and replied, "You can if you freeze it."
 
#24 ·
...
The lens is only held in place by friction with the gasket. After fussing and finagling with it, I found that the only way I could put the thing back together again was to unscrew the weird studs, take the reflector portion back out of the housing, then fit the gasket around the reflector, push on the lens, and then shove both of them into the housing. Keep that in mind if you need to replace the bulb.
...
So to replace the bulb in the "turd", you have to pull off the plastic lens?
Good tip too know.

Very good write up on this. Good work.

Carl
 
#25 ·
Nice writing, thanks.

"It's better than it was, and I replaced the 1156 bulb with an LED array, which means I shouldn't have to open the thing up again. Of course now my "bulb out" idiot light is on, but I'll deal with it. "

May be your cruise won't work properly with the LED bulb (?).
 
#27 ·
May be your cruise won't work properly with the LED bulb (?).
Hmm. Hadn't thought of that. But, I have a couple of 6 ohm 50 Watt resistors coming in the mail. When I added relays to both headlight circuits, putting one of those in the circuit fooled the idiot light controller so that the light didn't go on with the headlights.

As far as how to replace the bulb, yes, it's better to remove the whole assembly, as I'd mentioned above. The problem is that the odd shape of the lens makes it difficult to get the gasket and lens back in correctly. I tried that repeatedly and couldn't get it into place correctly.

The odd shape of the lens, which has a lip around it to hold onto the gasket, and the narrow clearance around the inner side of the housing makes it difficult to put the gasket on the lens or into the housing before you try to get the lens back in. I don't know why they just didn't put in a couple of screws like every other lens on the car. Again, it points to the likelihood that they let some intern design it.

And you want that lens to seat correctly into the housing so that it doesn't go bouncing off the road behind you, which you won't notice until the next time you go to open the trunk, or the cop cites you for having a naked bulb.
 
#29 ·
Another point to remember: when you put the assembly back on the trunk lid, make sure the gasket between the turd and the lid is securely in place. Otherwise you'll end up with a wet spare tire well, rust on all sorts of places on the lid and trunk, and the turd nuts will rust into place so that when you next go to remove them the studs twist out of the plastic which will strip and/or crack.
 
#31 ·
Further update. I figured while I was monkeying with brake lights, I'd replace the incandescent 1156 bulbs with equivalent LED arrays. My thinking is that I need not worry that a bulb will have blown at an inopportune moment. Well, that and I just like to monkey around with such things just to see what'll happen.

As I said above, though replacing the 3rd brake light bulb with an LED type doesn't affect the cruise control, replacing the other two brake lights will affect the cruise control function, as the cruise control amplifier needs to see a ground through the brake light circuit because the cruise control needs to shut off when you hit the brakes.

The solution to this, if you install LEDs in the brake lights, is to wire a 6 Ohm high wattage (in this case, 50 Watts) parallel to ground to one of the brake lights.

If you want the bulb out indicator to function correctly on the other bulbs (marker, back up, etc.) you'll need to add a similar load resistor to any bulb you replace with an LED type.
 
#32 ·
New for 2016. The search for a turd replacement continues. The repairs I did above, two years ago, have not lasted. Again, the plastic has cracked on the housing. Since I was afraid the lens was going to fall off somewhere on my 3,000 mile round trip up and down West Coast last year, I glued the gasket and lens onto the housing so that I wouldn't have to retrace my steps looking for it. Although I wouldn't mind taking a second such journey, I wouldn't want to spend it looking at the side of the road for my lens.

As for possible replacements, I found this site

Black Shrouded Brake Light Red Lens 200mm - Car Builder Solutions - Kit Car Parts and Accessories

has an aftermarket third brake light that is at least less conspicuous. It measures 200mm x 100mm x 36. It's 20mm wider than the MB one and about half the height. The depth is 50mm shorter front to back, but I just measured from underneath, the placement of the fasteners, and 100mm depth looks like it would just about cover the holes in the lid.

They're in the UK. Price is £11.40, including 20% VAT, but not including shipping, which might be £8-10. The pound is at 79 cents, which would put total price around $20 US. I will delve further, but a finger of single malt is calling me.


Red Light Automotive lighting Automotive exterior Auto part
 
#36 ·
Panzerpuff found this Jaguar 3rd brake light on eBay for sale right now. JAGUAR XJS 1995 THIRD BRAKE LIGHT ASSEMBLY TESTED | eBay
thanks for the note and keeping the threads on subject.
No one seemed to like my solution:devil
Supposed to get sub 0F tonight, so put the 300cd away for a week or two, until it warms up a bit:eek
Bigsky, maybe I missed it but I don't see a prior post by you so I was unable to like your solution. I don't have a spoiler. Cheers.
 
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