6 volt position ground

[Deleted User]

Couple questions if any one can help...
My Hornet (54) is currently 12 volt neg. Ground and re-wired from owner before. Back in the day was this auto 6 volt positive ground .
I'm asking because no gauges work nor does the horn,heater etc... If I wanted to start cleaning this up I'm assuming I have to drop the voltage or send the gauges out to get reworked ....

Park_W

Yes, the car would've been 6v positive ground. Don't mess with the gauges themselves ... there are several ways to supply them with regulated 5v that they need. Puzzling that they don't work at all ... if the car were merely changed to 12v neg ground the gauges should work, but read slightly high.

[Deleted User]

park W you are correct ,I wasn't clear. Your input is correct ...

[Deleted User]

The reason they dont work at all may be whoever converted it didnt know what to do, so theft them unhooked ?
Roger

DocHornet

The gauges don't care about polarity. It's just a little electromagnet coil inside each, and it doesn't matter which way the power circulates.

Pick up one of those early 50's Ford instrument gauge regulators at Napa.. 1 of these inexpensive units will be able to drop down the voltage for all your gauges.

Park_W

I recently tried to buy one of those early 12v Ford units, and NAPA no longer carries them. Dennis Carpenter has a good one.

[Deleted User]

I run a voltage reducer in-line from the ign switch to the heater switch on my '54 Hornet. It drops the voltage BEFORE it gets to the heater switch, otherwise the switch gets really hot...Only remember to mount these various 12 to 6 V reducers where there's good airflow, like the engine compartment, because they convert the excess voltage to heat and can get pretty warm. (Exception is the unit for the guages...) You can get 12V relays for the horn too pretty easily.

Park_W

Rudy, it really doesn't matter which side of the switch the resistor goes on ... inserting it anywhere in that circuit reduces the current "all along the route."

And folks, note that the the typical 12 to 6 voltage droppers are intended for circuits drawing about 5 amps. If the circuit carries significantly more or less current than that, the voltage reduction will not be 6v but higher or lower depending on the current (with higher current, the resister will "absorb" more voltage).