Blowing right headlight bulb

bobpo

bobpo

Well-known member
At first I thought I was doing something wrong, now I can't figure it out. I'm using 32-50cp bulbs and each time I try them, I blow the right one.

Any ideas? I can't find a short..
 
attach a wire to light bucket and a good ground and then try bulb! If it does'nt blow its a bad ground from bucket to bar to body or in the socket if you have original style.www.whidbeymodelaclub.com It's Almost Spring!!!!!
 
Yes, it sounds like a poor ground... , or check the wires in the socket, they may be causing an intermittent short. Hint, cover the springs with shrink wrap.
 
I tried adding an extra ground wire, everything suggested; mine still blow once in a while. I've examined them closely and I think they're breaking. It always seems to be broken where the filament is crimped at the end. Maybe too much vibration. I might try sealed beams or halogen. good luck, let us know what you find
 
I've heard this many times and I don't understand it. Why would a bad ground blow an incandescent lamp?

I would think a bad ground simply causes less current to flow through the filament. Am I missing something?
 
There is a reason behind this... read about it on "The Model Garage" website, which is a compendium of the Gus Wilson stories from Popular Mechanics' from the 1930's thru the '70s. Don't recall the specifics... I'll see if I can find it, and post a link.

I've not had terribly good luck with the modern Asian 50-32CP bulbs.
 
Had this happen to me, turned out to be the socket at the base of the bucket was shorting out. Eliminated the socket and everything is just fine.
 
Mike V,
You know, I'm not sure. I just turned the headlights on again yesterday and Lo and Behold, the right light was blown. I used all new wiring on my 'A' and I used good solid connections and then shrink wrapped all connections. BUT, I haven't really checked the ground. I didn't use the old sockets.
I'm thinking the bucket contact....
 
MrTube said:
I've heard this many times and I don't understand it. Why would a bad ground blow an incandescent lamp?

I would think a bad ground simply causes less current to flow through the filament. Am I missing something?
Click to expand...


Here's a link to the "Model Garage" article I was thinking of... not about a loose ground per se, but about loose connections and their impact on automotive electrical systems and lighting.

Bear in mind that the problem car in the article (from 1942) is a "typical early '30s car", with a third-brush generator and cut-out.

http://www.gus-stories.org/may_1942.htm

If the link doesn't work, go to "www.gus-stories.org" and look for May 1942: "Gus spotlights lighting troubles"

I will post links to other vintage Model Garage headlight articles under a separate thread.

:cool:
 
The reason why bulbs blow out with poor grounds and vibration is that when you turn on and off a bulb there are tremendous heating and cooling of the filaments which causes the filaments to become more brittle vibration causes the filaments to break more readily since they become brittle. Leaving an incadescent bulb on continously makes them last longer, but cost more due to electrical costs. As a side note, years ago when most Military electronic equiment that was made that had tubes, there was a standby mode that left the filaments of the tubes on and turned off the high voltage only. Tubes lasted longer by doing this. A electron tube is a highly modified light bulb.
 
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