The Stovebolt Site Forums The Shop Area The Electrical Bay 6V switch, 12V bulbs?

Electrically challenged here, so I hope these questions aren't too dumb.

First, my '48 GMC has been converted to 12V, negative ground. The wiring harness has been replaced with a modern kit that included a new headlight switch. It also has new, modern gauges. I don't like the look of the switch and am wondering if I can use an old 6V headlight switch in place of the ugly new one.

Second, I've replaced the new, non-functioning speedometer with a good original one and want to know if I can splice in the original 6V instrument light sockets and use 12V bulbs. The new wiring is a smaller gauge, numerically higher, than the old 6V wire.

As always, thanks for your help! Jim

Should work fine. Not sure if your old switch has a built in dimmer. That could be affected? Higher voltage less current that,s why smaller wire is okay. Using a 6 volt socket with a 12 volt light should be fine.

X2. Switches and sockets don't care about voltage. They care about current which is lower with 12v than 6v.

Thanks GWWirth and Tiny. I was pretty sure it would work, just wanted to make certain.

The old 6V switch I'll use still has a short length of the original wires attached, though they don't match up exactly with the wiring diagrams I have. Still, I should be able to figure out what goes where.

What would be the best way to clean up the old switch? It's between a little grungy and sorta dirty---not scientific terms but I hope descriptive enough.

Thanks again. Jim

Hard to say without seeing it. Make sure you have continuity (the circuits are good) before you spend a lot of time purtying it up. A multi-meter is best for that.

Clean the switch with brake cleaner. Look at the can it should be alchohol. Safe to use on the switch. You can use compressed air to dry. Look for the contacts at the rear of the switch. They are the "circuit breaker" for the headlights. if they are clean and straight it should be OK. The last bit to look at is the ceramic disk at the front. That is the dimmer control. It should be clean and the nichrome wire should be unbroken. After that you should be good to go. As previous posters have said, a 6 Volt switch(automotive only) is rated at more current than a 12 Volt switch. Current matters. Volts, not so much.

Continuity looks good and the switch seems to be working according, to my multi-meter. Preliminary cleanup went well, everything looks intact. I don't think I'll go too crazy on the purtying up but a little cleaner would be nice.

Thanks, Guys. Jim