blinking 1946 Cadillac headlights

I am having problems with my 1946 Cadillac (all stock) headlights blinking after being on for a few minutes. The bimetal circut breaker tab on the headlight switch gets very hot 190 deg. I have changed out the dimmer switch and headlight switch with used parts and no change. I have checked all grounds and ran a ground to wire test wih an ohms meter and no shorts show up. I know that I can install a headlight relay to rduce the heat on the headlight switch, but that just seems like a bandaid. Any suggestions would be very helpful thanks Dave T

 

I had a car do that driving down the road and it was a wire shorting to the sheet metal. Check how much current the lights are drawing. I think the breaker only feeds the headlights.

 

Check to make sure your grounds are good to the headlights.
Bad grounds can raise current draw!
KK

 

Sounds like you have a high resistance connection somewhere. Try cleaning all connections so you have clean metal to clean metal. Electricity trying to find it's way through a corroded connection will meet with high resistance and create the heat.

 

Install a headlight relay circuit. That way, the headlight switch and dimmer need only control the current for a couple of little electromagnets rather than the big filaments. It is not a band-aid. It is the proper, modern way of doing it.

Modern headlights are brighter (higher amperage requirements) than old ones, especially halogens, and especially ones like Sylvania Silver Stars.

Even a brand-new switch in my 96 Jeep was not up to the task of Silver Stars, and they started to blink. Installed a pre-made relay harness: problem solved.

 

I-E/R I is the current in amperes. E is the electromotive force in volts. R is the resistance in Ohms.

From the formula, you will see that as resistance increases, the current decreases. The heat in the light switch is caused by current flow. Bad connections can cause heat at the point of the bad connection so unless the bad connection is on the light switch itself, it won't cause the problem. The OP has tried a different switch and likely would have noticed a bad connection there.

 

6 volt relays might be hard to come by. Hella has one I think. You could use a horn relay but it might not last as they're designed for intermittent use.

 

try this - get a small jumper wire - alligator clips & ground each headlight - mounting base to engine or frame - see if the problem disappears?? if so the groung is bad on the light /s

 

Bosch 0 332 204 001. About $20.

 

Was the car a 6 volt originally and now your using the same switch to run it on 12 volts?