Tail/brake light bulbs loose?

[moneymanager]

I have now known well or owned three early 911's with a total of six taillights. Over the years I have had to stuff aluminum foil or a toothpick or something into the light sockets of each and every one of them to properly secure the tail/brake light bulb. In my experience, there doesn't seem to be a problem with the other lamps, only the tail/brake lamp. My latest difficulty involved a tail/brake unit which had broken at some point in its life, been repaired by a PO, and worked only intermittently as a taillight and almost never as a brake light. Somehow the little brass tabs inside the socket which are supposed to contact the bulb didn't.
Yesterday I decided I wasn't going to take it anymore. (Nor was I going to lay out over $300 for a 2.8 lb piece of cast pot metal to replace the aging unit in the car.) For the princely sum of $4.50, my local Car Quest provided an S-27 Socket pigtail assembly. After pulling the taillight, I opened the box, pried off the back of the offending socket, and drilled it out so that the new socket would almost fit. I was looking for a force fit to ensure a good ground. I then took the small aluminum "arms" off the new socket, leaving just a cylindrical unit to slide into the still too-small hole. A bit of filing with a rat-tail file got the hole just right and, presto, with a few taps I was able to gently "force" the new socket into the old hole. It fits very tightly, providing a good ground. Best of all, the bulb is now held very securely in position by two sturdy springs inside the new socket and the tail light and brake lights work perfectly, never flickering or blinking as I drive on bumpy pavement.
Picture 1 shows the stock but defective previously repaired socket. The second picture shows the new socket pressed into position...there is a small lip visible just below the bulb which is part of the new socket. Picture 3 shows the back side of the new socket...one wire is for the tail lamp circuit and the other is for the brake light circuit.
Make careful notes about which wire goes where to ensure you wire the brake and taillights correctly, and don't forget to wire in the small bulb at the other end of the fixture which is "powered" by a green wire from the (red/grey) wire to the tail lamp. It is possible to connect the black/yellow brake wire to the low watt connection on your new socket, and the red/grey tail light wire to the high watt connection. This would give you a very bright taillight augmented by a hardly noticeable brake light...just the reverse of what you want...so wire things together temporarily and check to be sure you have it right.
I'm hoping there is someone somewhere who has experienced this annoying problem and who will benefit from all this bandwidth

[Porsche-O-Phile]

The alloy used in the taillights is very brittle. Those metal tabs that hold the brown "circuit boards" in place are very, very easy to break off.

I just got done rebuilding my taillight assemblies and secured the "circuit boards" with (don't flame me) JB Weld across the back. For that particular application, the stuff works great. I also painted and POR-15d the assemblies, and changed all the bulbs to LED clusters. Much better overall. I'll do a write-up in the next day or two.

I like that setup you have, although I just yanked the circuit board things out and cleaned the heck out of the copper/brass contacts and the insides of the bulb sockets with a metal file. No problems whatsoever now.

[moneymanager]

I've run into JBWeld two or three times...works fine if there is enough metal to hold the "circuit boards" in the proper position. On mine though the board when glued in wasn't properly aligned, leaving the brake light disfunctional and the bulb rattling around. I like the led idea though. Please show some pics.

[rusnak]

that potmetal is difficult to get anything to stick to.

I thought about this too, since my backup light has trouble sometimes.

I eventually found a very good solution by soldering some additional material on to the bulb contact, thereby ensuring a good contact with the copper tab. I think I had to experiment with lead, silver, etc. finally got some lead solder to stick to the bulb, and presto no more problem.

[ChemMan]

Thanks. This will be very useful!

[moneymanager]

I think the best idea here might be the led conversion... which would seem to fix all these problems for a very long time. Rusnak, I admire your soldering ability. I couldn't augment the contacts on the bottom of a tail light bulb without about 100 hours of practice. My solution should last pretty much forever and it won't take much of your valuable time.

[HarryD]

Money:

How has your fix held up? I will need to do this to my 1973.5 to get the lights working again.

[moneymanager]

Was the perfect solution. I later added an LED "bulb" for brighter light. Well worth the money.

[NO LIFT]

I've got the tailight problem...loose bulbs, bulbs not grounding. Tried pulling the contacts so they're tight, O-ring on the bulb, etc.

So, I wanted to do as described in this thread.

But, I can't remove the screws that hold the housing in. They back out, but then whatever holds the back just spins.

Should I drill 'em out?

[moneymanager]

Since doing my conversion and adding the LEDs, I don't need to get in there anymore so my memory is dim!
I'd think drilling the screws out would be tough, they are at least 2 inches long I think. Can you see what's going on from underneath with a flashlight? Is it possible you have got them free of the body and all you need to do is just pull the housing out with the screws in it? (May take some effort.) As I recall they just go thru the housing into the sheet metal behind.

[NO LIFT]

Reached behind light housing, can feel the back of the screw turning. Some kind of a square flat fastener thing that turns with the screw. Now I've got it stuck loose! Tried holding the fastener that the screw goes into, still can remove the screw, and now it won't tighten either!

Thinking of trying this as an alternative:
rear tail light housing bulb ground repair

LED's seem to be a great improvement, lot's of info in other threads. Can anyone recommend the latest and greatest LEDS that don't need a resistor?

[moneymanager]

Go to SuperBrite. Outermost bulb is a red BA9 I think. The second one in from the outside won't work without a resistor which is hardly worth the trouble. The third one in is the backup, and the innermost taillight/brakelight takes a 1157 R (“red”) LX5 series with 5 watts (a Luxeon 3 watt LED + 4 smaller surface mounts LEDs & an excellent 180° degree beam pattern.) Very bright.

[BarryJB]

I've been using brass shim, similar to burgermeister's fix, for a few years but it's no longer doing the trick, the contacts are just too weak and even building them up on bulbs or bending the spring strips no longer helps for long.

Local Auto stores sell a selection of replacement bulb holders, in US, foreign & generic auto types, for the single & double filament bulbs of the bayonet (and more modern blade) type; at least some of these have a ground wire or terminal on them, rather than relying on their contact with the housing. Some have plastic shells that twist-lock in, others have metal fingers like a hole plug, others are just minimal metal sleeves. But prices are cheap - in the $3-$10 range per holder.

I plan to pull off a rear light unit (hopefully this weekend) and go buy a selection of the replacement holders, and see which will retrofit best/easiest - i.e., gonna cut off/drill out the originals to accommodate something that works; twice a week on my knees with a screwdriver in the parking lot messing with intermittent bulbs is enough!

Will post any good findings here once the dirty is done...
Cheers
Barry

[SchnellSchweitz]

No Lift:

Get yourself a set of these and grab hold of the square "speed nut" at the back. You may need to flex the wrench a bit to get the threads to grab. Often they strip.



I usually lay on my back, with the phillips screw driver already in place and one hand on the wrench. If you work at it... they do come off. It does pay to replace these with OEM screws and speed nuts from Pelican once you get them off.

[HarryD]

Barry,

I had a similar problem with my brake light. It would go out but would work again if I wiggled it to the correct position but would soon lose contact with either the ground or 12 volt power and go out again.

I finally went to my FLAPS, bought a $2 universal replacement socket, removed the tail light assembly from my car and opened the back. Using my Dremel, I enlarged the hole in my tail light assembly, tapped it into place and installed the socket. Problem solved!

Cost $2
Time 1 hour

[BarryJB]

Originally Posted by HarryD

Barry,

I had a similar problem with my brake light. It would go out but would work again if I wiggled it to the correct position but would soon lose contact with either the ground or 12 volt power and go out again.

I finally went to my FLAPS, bought a $2 universal replacement socket, removed the tail light assembly from my car and opened the back. Using my Dremel, I enlarged the hole in my tail light assembly, tapped it into place and installed the socket. Problem solved!

Cost $2
Time 1 hour

Harry,
Yup! Car has >340k on body now, and that's exactly my issue with pretty much all of the rear bulb holders... very encouraging, and unlike springing a grand on new units & lenses, leaves time & funds to enjoy a beer or two while admiring results for months to come. I'd like to use sockets that have (or have or allow a way to attach) a ground wire, so I'll also eliminate another little annoyance - or add a new one .

Although $50 and all day will still be getting off lightly - unless I can keep "while I'm in there" at bay.

[HarryD]

Originally Posted by BarryJB

Harry,
Yup! Car has >340k on body now, and that's exactly my issue with pretty much all of the rear bulb holders... very encouraging, and unlike springing a grand on new units & lenses, leaves time & funds to enjoy a beer or two while admiring results for months to come. I'd like to use sockets that have (or have or allow a way to attach) a ground wire, so I'll also eliminate another little annoyance - or add a new one .

Although $50 and all day will still be getting off lightly - unless I can keep "while I'm in there" at bay.

Mine is a press fit and works just fine. Why make it complicated for a $2 part.

[BarryJB]

Originally Posted by HarryD

Mine is a press fit and works just fine. Why make it complicated for a $2 part.

Different strokes, Harry, no criticism intended, I expressed appreciation for your post and meant it.

I guess you missed my self-mocking "or add a new one"?

Cheers
Barry

[BarryJB]

With tail light assembly off and with several generic sockets on hand, intending to replace most of them, I found that the following TLC has fixed the intermittent thing when you wobble the bulbs, plus a way to refasten the stop/tail "circuit board" - or the others.

It seems that on my car, corrosion or dirt on the socket bores was preventing a good solid ground even when the contacts were bent up & tight - simply wobbling the bulb gently with your fingers would make then go on and off, and in their normal twist-locked position was when they were most prone to fail otherwise.

TLC: On the tail/brake light socket, broke off just one of the tangs, releasing the board, then bent both parts of the contact strips up - pretty sure on earlier attempts with just the tail light lens off, with a dental pick, it never caught the "hidden" helper strip under the brass (or whatever it is) contact strip; buffed them with 1000 abrasive paper, and gently re-peened the (aluminum?) rivets. Used a battery terminal brush to clean the inside of the bulb socket.

Then (see pics) used a #42 drill in the meat of the pot metal, down through the side wall of the socket (the one opposite the remaining tang) from the rear, all the way through; then put the circuit board back in and drilled back from the lamp side through the board, to get the hole in the right place.

Dremeled a notch in contact as shown so it wouldn't ground on the small self-tapping screw, also added a little piece of heat shrink - (loose on screw or it's impossible to angle board back in under remaining tang) and a washer. Screw (junk box) is the type used into plastic in consumer electronics & small appliances.

Obviously one could drill both sides if both tangs were busted off; or there's room to drill the reflector surfaces outside of this, or the other sockets, which would allow a little strap across the top with some longer screws on the outside, if one wanted to rebuild the circuit boards with odds & ends and not have to worry about breaking off or reusing the tangs.

The turn signal holder has been my biggest aggro, but just using the battery terminal brush on the socket bore and bending up both parts of the contact strip has fixed it. This one would be a challenge to replace as the side marker is so close to it, and it looks like the holder also retains the reflector. Plus I measured all the FLAPS sockets I'd got and none of them were short enough to fit there, one style was close, maybe modded to fit, or not fully pushed in to allow clearance.

It appeared to be (old dried up) plumbers putty sealing the back plate, so used the same to reseal...

Maybe a little more than some folks feel is worthwhile, but then messing with this stuff is part of the fun for me.

So all the sockets go back to the FLAPS, unused - for now

Cheers
Barry

#42 hole drilled from the back - screw goes in from this side; view from bulb side with "circuit board" installed using the screw.


Showing dremeled notch, and screw/heat shrink detail

[HarryD]

Hi BarryJB:

I thought I had a grounding problem as well so before I did the aftermarket socket, I uses a strip of thin metal to shim the bulb into the socket. I found it did not help. I think the slots that the bulb "ears" lock into were so worn it allowed the bulb to rotate and the pins to lose contact.

That said, your solution is quite elegant.