My dome light housing melted.
Actually it melted a long time ago, but now i have a new one and don't want it to happen again.

The one that melted was a replacement. I think I threw out the original. Stupid.

First question: Was the original housing plastic like the replacements?

My chrome on the original was pitted, which is why i question whether it was plastic, but mostly it's why i replaced it. I never had a problem with it before, but I also never had a lens on it before. I noticed the lens had a brown spot and upon inspection, it was clear that the bulb had melted the housing... glad I found it before it melted the wires or caught fire to the headliner.

I always had a 211-2B (blue) bulb in it. The specs are the same as the 211-2 and the OE 211-1 bulb.

Any thoughts on why the bulb melted the housing, and what I can do to stop it from happening again? For now I left the lens off to help dissipate the heat.

Is it me or is there a Chevy bowtie in the middle of your light? Obviously the original was replaced with this cheap substitute at some point! Buy only Pontiac parts!

Oh - YOU replaced it. Be more careful, you now know what can happen when you cross-source!

Good call.
How do i keep the bowtie from showing up again?
BTW, you might enjoy parts of my latest blog entry "my car is not a camaro"

I bought the melted one from either classic or paddock. The new one is from CPU. No bowtie yet.

Scott, my car is a convertible, so I don't even have the option of owning one! How do I get to your blog?

click on the picture of the shock absorber in my sig to get there.

Scott, they all fade and do a little melting as the years go by. Use the lowest wattage bulb, and most important ensure that the two electrical connectors holding the bulb are tightly screwed in and secure. Thats the most common heat problem. That, or you had too high of a wattage bulb.

Do you leave your door open alot????? When smooching with your babe in the bird, turn all courtesy lights out! Use the dashboard lights to have your fun.

Do you have a part number for a lower wattage bulb than the stock one?

You said blue bulb? Wouldn't a colored bulb tend to be hotter than a clear bulb? Unlike a clear bulb in which most of the visable spectrum passes through the glass, I would think that a lot of the light gets absorbed by the bulb's glass and converted to heat.

Our Christmas lights with clear glass don't get anywhere near as hot as the colored ones.

That's the answer I'd been waiting to hear. Thanks.
I had a suspicion on the blue being hotter, but with the same specs, I couldn't think why.

Rig up a test with a clear and a blue bulb and some alligator clips, wire and a 12v battery. Run them a few minutes and see if my theory holds.

I bet the blue will be hotter over time, or any colored lense. The dye or coating causing the color would probably retain more heat than a clear bulb. Sounds quite probable in theory.

I'll try to do the test tomorrow and report. I wish i still had my temperature laser
I'll have to rely on my sense of radiant heat... it's like a superpower

It totally makes sense though. Even though the original was not at all melted, it also never had a lense on it. The lens helps retain the heat I'm sure. I really like the blue light, but I think having the lens is better. I don't remember how long the light had been on once i noticed the problem, but I probably had the door open for a while working on stuff.

The blue one seems quicker to get hot, gets hotter, and I can feel the heat from further away. I rigged them both up on a battery charger, first in-line, then individually.

Mine did the same thing while it was in the tint shop. They had the doors open for a while and when I got the car back, the light didn't work. A few weeks later I looked into the problem and mine looks just like yours. Had a clear bulb in it. I replaced it with a repro one and have since removed the tint for a more classic look.

I haven't looked into a lower watage bulb yet, I just don't leave the doors open long or pull the fuse.

I was trying to find a brighter bulb for my hood tach and ran across this info: http://www.theherd.com/articles/bulbs.html

Unfortunately, it doesn't list the specs for 211 series bulbs, but you can see that wattage varies quite a bit between different # bulbs of the same base style.

Just take an ohm meter to the parts store and pick the bulb with the highest resistance.

Probably the most significant thing you could do to avoid future melted lens covers would be to make sure the dome lamp always goes off when you shut the doors. And don't leave the door's open while working on your car. Damage to the lens from bulb heat is almost certainly a matter of many minutes or hours, not the brief time needed to enter your car.

Surely the factory would have forseen someone leaving the door open long enough to run the battery down. I've done it on other old cars, and probably this one before I put a lens on it.

The lens itself barely has a mark. The chrome housing though looks to me like it got hot enough it could actually have caught the headliner on fire if left long enough.

Anyway, the lowest wattage one I found was a 214-2

Recently I had the opportunity to check operation with the clear bulb. I had the door open while running the engine, and luckily remembered to check the dome for heat after maybe 5 minutes. The lens was pretty hot, so i took it off. The housing was already bulged and flaking the chrome off around the bulb. This sucks. I shut the door, but I really ought to be able leave it on and forget it w/o destroying my car. WTF is going on?

My local parts supplier-restoration shop has had issue with the reproduction dome lights. He said it comes from them being Chromed plated inside and out. The originals were only Chromed outside.

I was ordering one when he told me this. He was going to tell me what he does to fix it but we got side tracked on other things. I'll ask him again when I see him to pick mine up.

He's seen several cars catch fire or do the melt down like yours. If your replacement is Chrome inside it will do it again.

Thanks for the info.
I'll take mine down soon to check.
I bet it's chrome inside.
I'll try the wire brush wheel on the topside to eliminate the chrome. At least they're kinda cheap if i mess it up.

On a side note, kinda related...
One of my front marker housings on my '68 was very corroded on its reflecting surface, making it dim, so i lined it with kitchen foil, shiny side out. It's VERY bright now. I did both to make them even. I prob'ly have the brightest markers you've seen they haven't melted yet.

I don't buy the all chrome causing the problem. If someone could explain the logic behind all chrome causing the problem, I'm listening. Because I cannot see the common sense behind that best guess, I'll put forth my best guess. This is a text book example of a high resistance, either at a connector or most likely at the point of ground. Try cleaning the jam switches. Use some electrical switch cleaner, depress the switch, and let the switch snap open. (Watch the switch cleaner around vinal.)

Quote: "One of my front marker housings on my '68 was very corroded on its reflecting surface, making it dim, so i lined it with kitchen foil, shiny side out. It's VERY bright now."

Well it is Christmas time Scott! Watch out for them NC State Police at dusk, they'll see you coming!