I've switched my 54 chev to 12 volts. I have bought two dropping resistors, supposed to change 12 to 6 , but both read 12 on both sides, What am I doing wrong?? Need 6 for my heater and radio, thanks

The load must be connected and current flowing in the circuit before there is a voltage drop across the resistor.

Right on, D2D2

Ohm's Law.

D2D2, was that guy Ohm one of those old timey Monks in a Monastary that sat around saying"Olm, Olm, Olm"? I think he probably was!

German physicist Georg Simon Ohm (1789-1854)

It is not recommended to operate a 6-volt radio on a 12-volt battery by use of a dropping resister. When the radio is first turned on it receives the full 12-volt blast

And that's just one of the reasons not to convert a 6 volt system to 12 volts.

Where did you purchase the dropping resistor ?. I'm running into a similar problem where I need to step down the voltage in a heater fan and the horn, after switching to 12 volts. Thank you for help. HotPockets

A previous owner converted the system to 12 volt. Just for grins, if I wanted to go back to a 6 volt sytem what would I need to do? I figure at a minimum the voltage regulator and battery would need to be changed, maybe the generator was somehow converted too? How about the wiring harness, I'm thinking no change out would be needed there? I know they installed a voltage reducer for the fuel guage and that would need to come out.

coil and generator and i believe the condensor in the distributor. also check the starter---Bubba may have left the 6 volt starter in place as they will live a while fed 12 volts(and they spin like crazy). replace battery and remove any resistorsBubba added.wiring harness , if original, can stay.horns if 12 volt will need replaced, but here again, ole Bubba usually left the 6 volt horns in place as they too live a while with 12 volt feed. mike

What a tangled up mess. Still amazes me that folks even think about converting from six to twelve volts.

I can understand it if a car is completely changed around, like V-8 and big mods like that. Otherwise 6 to 12 on a more-or-less stock, original car seems like a big can of worms.

Maybe if I was more of a mechanic, it'd make more sense. Due to being a mechanical dummy, it's all way past me. 99% of the time it seems like a half-baked job or something doesn't work out or....

Bill.

Filling Station sells these and probably your local auto parts store. I saw them at AutoZone recently and I'll bet NAPA and the others stock them too.

I purchased one at my local auto parts store.

Can these be soldered instead of using connectors?

They can be soldered but not sure why one would want to do it. Make sure to use rosin core solder and not acid fluxed. Much more of a problem to remove or replace.

Chipper:
Thanks. Believe me I'd prefer not to solder, but in working under the dash I managed to bump the wire connected to the gas guage and snaped off the resistor wire leads about 3/8 of an inch from the ceramic part. I was considering this option in lieu of replacement.

I soldered a 14 gauage wire lead with a connector to each end of the resistor. It checked out at 25 ohms with a meter, which is the rating given on the resistor. Before I connect this to the under dash wiring is there any other meter test is should do? I want to avoid ruining the gas guage. Bear in mind I'm climbing a learning curve with this stuff. Thanks in advance.

To close the loop on the resistor soldering question I connected everything up and all worked fine. Learned a lot about wiring and such in the process. I had forgotten for example that resistors do not have polarity. The last electronics class I had was toooo many years ago.