C3 Headlight Switch

[David C.]

[Edward J.]

Re: C3 Headlight Switch

David the switch will come a part once you have it out, there s a metal plate with some tangs that are bent over that can be removed, use some dielectric grease to lube.

[Jimmy P.]

Re: C3 Headlight Switch

Hi Dave,
Yeah, I was getting ready to post a suggestion but Edward beat me to it. Below is a photo of the switch pointing out a couple of the tabs Ed mentions. Since you seem like you aren't really sure if you want to remove the switch, why not try the grease on the new knob stem to see if things loosen up. Please remember to DISCONNECT YOUR BATTERY before messing with the switch trying to get to the knob release button on top of the switch. I'm not sure if the switch is causing your lights to lag when closing though!
Happy New Year!

[Dan D.]

Re: C3 Headlight Switch

David the switch will come a part once you have it out, there s a metal plate with some tangs that are bent over that can be removed, use some dielectric grease to lube.

Sorry Ed, but I have to disagree with you on the dielectric grease. Dielectric grease is non-conductive and you do not want that on electrical contacts. Dielectric grease is used on spark plug boots and electrical connector boots to seal out moisture and prevent high voltage arcing. You do not want to use it where you want electrical contact, such as on the sliding internal contacts of these switches. You could use it on the switch shaft, but don't use it on the internal switch contacts.

What I use is Dow Corning Molykote G-n paste (photo below). While designed as a high pressure lubricant, it has excellent electrical properties and is electrically conductive. When the vehicle evaporates, as it will do over time, the solid graphite's remain and provide lubrication and maintain electrical contact for a long time afterward.

Of particular concern with these switches is the rheostat. These are prone to failure and if the switch is dry, as it sounds like it is, this will wear the wire coils and they will eventuality break, and you will have no instrument panel dimming. Rheostats cannot be repaired, and finding good used switches is very difficult. Reproduction switches often have incorrect electrical resistance in the rheostat, and the internal circuit breakers are another issue all together.

If your switch still works, as you say it does, the switch should be dissembled, cleaned and re-lubricated. If this is something you don't feel comfortable doing, I can do this for you if you want. I am just finishing up doing a 66 switch for another member. I have a test setup for this which includes testing them under a high current load. The second photo shows a mid-year switch undergoing test at high current after I re-adjusted the circuit breaker, which was set at an incorrect current trip point. What you are seeing in the photo is an air cooled resistor load bank. The power supply and current meter is off to the right and not in the photo.

-Dan-

[David C.]

Re: C3 Headlight Switch

Thank you all for your responses, and happy new year to you!

[Brian W.]

Re: C3 Headlight Switch

On my '68 the dash lights are either on or off. There is no way to dim them. I think there is a problem with the rheostat can it be repaired or should I get a new switch?
Brian

[Dan D.]

Re: C3 Headlight Switch

Pretty good bet Brian that the rheostat is toast. There is no way to repair the rheostat. When you get the switch out you can easily see the rheostat and see if the wire is broken. Best bet would probably be a new switch, but reproduction switches have a bad track record. And used ones on e-Bay and such places - well there is no guarantee they are any good either. Sorry I don't have better news for you.

-Dan-

[Brian W.]

Re: C3 Headlight Switch

Thanks Dan the hunt starts now.