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I purchased a harness from Jim Carter to convert my 6 volt 52 Chevy truck to 12 volts. I'm not sure what gauge wire it is, but it's for 12 volts. Now I'm having second thoughts about making the conversion. Can someone tell me if a 12 volt harness can be used on a 6 volt system without problems? Thanks.

12 V wire will probably be smaller than the wire needed for a 6 V system

What is JCs part number?

Will the system you end up with be 6v or 12v?

The JC name/part number is: Wiring Harness Type #2 1950-1952 with Generator PVC Copper Wire Chevrolet
Item # EL165C. I thought it did say that it was for 12 volts, but after checking the description, it doesn't say 12 or 6. The system will be a 6 volt.

What second thoughts? There are people both 6-volt advocates and conversion guys (like me) that can help. Can you outline your specific concerns?

Yep, I've read many posts on this site regarding the two schools of thought (6 vrs. 12). Right now, I'm questioning the need to convert to 12 volts.

The kit is not a "conversion" kit. It's a wire harness for 50-52. Which means it's meant for 6V, OK for 12V. The conversion is mostly component changes. It lowers the amps, maybe more common parts and more common/cheaper batteries. It's up to you. Your harness is useable either way. Your truck will run good either way. If you had a need, you would know it. Don't fix it if it ain't broke. Ammeters are dangerous however, so if you have one, be careful or change to a volt meter.

Not to hijack the thread, why is an Ammeter dangerous?

Most likely because they measure current in AMPs and have high current flowing through them where a volt meter draws very little current and measures voltage.

I hope this makes sense to you.

Thanks for the help folks. It's great the harness will work for 6 or 12. Three more questions; A concern I have with leaving the truck on 6V is the very dim brake lights. (1) Do the inverters that convert 6V to 12V work very well? (2) With an inverter would it make sense to replace my existing lights with 12V LEDs? (3) I've read that installing a relay for the headlights will make them brighter. Is that correct? Thanks for the help (I'm a rookie at wiring).

ammeters and voltmeters report on different things .... the current that flows thru an ammeter depends on the amount of draw of electrical items and the condition of the battery, as well as the generating item - the original 25-35 amp generator, with a good battery, and no added electrical bling shouldn't present any hazard providing the wiring is sound, not original cloth covered wires badly deteriorated - if you want to "upgrade" to a 80-100 amp alternator to power a bunch of electrical add-ons, new, heavier, wire can preserve the safety, but a voltmeter is generally recommended to avoid having all that current under the dash

Bill

DMG has the "short" answer, as in fire and burning up your truck. (Danger No.1). Not catching a problem with system, (Danger no. 2). Here is a tech article by AutoMeter, they probably know what they/the writer they quote, are talking about.


"Which is better for monitoring a vehicle's electrical system - a Voltmeter or an Ammeter?
Short answer:
A voltmeter, by far."


"Electrical guru Mark Hamilton of M.A.D. Enterprises points out that amperage is a measure of current flow, so an ammeter is actually a "flow meter" that's intended to measure current flow to the battery (under normal conditions) or discharge from the battery (in the case of alternator system failure). On a typical flow meter, all output must be directed through the device to obtain an accurate reading. In the ammeter's case, that means all the alternator output used to recharge the battery must first be routed through the ammeter under the dash. Which requires a heavy-gauge cable and presents a possible fire hazard. And the ammeter itself must be able to handle all this current flow, so it must have a higher current rating than the alternator's maximum rated output.

All this might be worth the hassle if the ammeter produced reliable information. But the ammeter can only measure the amount of current output to the battery for recharging purposes: When the alternator recharges a "low" battery, the ammeter indicates a high charge rate; with a fully charged battery the voltage regulator reduces alternator output, and the ammeter is supposed to indicate a very low charge rate. But how can you really tell the regulator has reduced alternator output because the battery is fully charged? Maybe a diode in the alternator rectifier failed, or the alternator belt slipped after it warmed up, just as if the battery were fully charged. Or maybe the meter indicates a medium charge rate most of the time-does the battery want this much or could the voltage regulator be overcharging the battery?

On the other hand, a voltmeter works like a fuel pressure gauge-but instead of measuring fluid in psi, the voltmeter measures electrical system pressure in volts. Just like a fuel pressure gauge, a voltmeter only needs to tap into a circuit; all the fuel (or electricity) does not have to detour through the gauge itself. Voltmeter installation is easy, quick, and safe: It hooks up to a fused, ignition-switched "off/on" source and does not require any modification of the circuit used to recharge the battery or any part of the alternator/regulator system. In short, the voltmeter installed at the dash will be a stand-alone circuit.
The voltmeter directly measures the result of charging-system performance. With normal alternator/voltage-regulator function, battery voltage is maintained at 14.0 to 14.5 volts-and this is reported directly by the voltmeter. In the event of alternator-system failure, voltage will be low and continue to drop as the battery discharges. In the event of an "overcharge" condition, the voltmeter will climb above its normal zone. In summary, there is no chance for misinterpreting a voltmeter's readings as can happen with an ammeter.
Voltmeter vs. Ammeter?

Auto Meter offers both, but for most applications a voltmeter yields a safer installation while providing more useful information on charging-system conditions."

What bulbs are you using? It's fairly easy to make a 6v tail light just about as bright as a 12v. My 6v '38 on the left/12v modern truck on the right.

rcborst,
1). Inverters work ok as long as you stay under their rated amps. Not really needed for tailights. Change out the insided holder and go to a larger bulb. sorry forgot the size bulb but it is still 6 volts.
2). I would only use an inverter if trying to go to 12 volt tailights.
3). YES - This is the major item to do if staying with 6 volts. It will accomplish two things, make the headlights brighter and save the headlight switch under the dash. This is caused by the switch only drawing the current required to pull in the relay (low current thru switch).
4). With 6 volt system one of the main items to stay on top of is keeping the grounds clean on both the battery and the frame of the truck.