6 VOLT to 12 VOLT
ELECTRICAL SYSTEM CONVERSION 

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Certainly, the 12 volt electrical system has many advantages over the 6 volt system, otherwise the automakers would never have converted.  Consequently, many owners of 6 volt vehicles have made the conversion.  But before you decide to convert, thinking it's a quick job, we would like to inform you about some of the electrical systems that will need to be addressed.  Once you have addresses all these systems, you can determine if it is worth your time, effort and expense to make the conversion.

WIRING HARNESSES
Assuming that your 6V wiring harness is not in poor condition,  no changes are necessary as the 6V wiring can easily handle a 12V system.

IGNITION SYSTEM
Starter: A 6V starter is designed to handle a lot more current than a 12V starter so you probably won't have to change the starter.  However, the starter solenoid should be replaced with a comparable 12 volt unit.

Ignition Coil: You should replace your 6V ignition coil with a 12V unit. Depending on the coil used, you may also need to add a ballast resistor.

Points & Condenser: As far as the points are concerned, you will see that your 6V points are made more heavy-duty than the 12V points and are able for 12V operation.  Consequently, the points do not need to be replaced.  You should replace the condenser with one used on 12V cars.

CHARGING SYSTEM
Battery: Obviously, you will need to replace your 6V battery with a 12V battery.  Before going to the auto part's store, check the size of your battery tray (and hood clearance), the type and length of battery cables you have, and which side of the battery the terminals go to.

Battery Cables: You do not need to replace your battery cables unless they are corroded or in poor condition.

Alternator: When replacing your alternator, the most common 12V alternator to consider is the General Motors 10SI unit. It has an internal regulator, and requires 3 external electrical connections.  You will also need to make sure you are able to physically mount the alternator as you may need special brackets or spacers to complete the job. You may need to modify your wiring harness to convert from a generator to an alternator.

GAUGES
If your vehicle is only equipped with warning lights (idiot lights), you can simply replace the bulbs and you're done.  If you have gauges, you can either install a dropping resistor in the feed line to the instrument cluster or replace them with later model 12 volt gauges.  You will also need to replace all the sending units to the respective gauges (fuel, temperature, etc.).  The Ammeter (amp gauge) does not need to be changed as it is not effected by voltage.

LIGHT BULBS
ALL the 6V bulbs in the car will need to be replaced with comparable 12 volt bulbs.  This includes headlights, tail lights, dash bulbs, dome light, parking lights, etc.  The 6V bulbs may last for a short time, but they will burn out.  You will probably find that some (or possible many) of the light sockets will need to be replaced in order to accommodate a comparable 12V bulb.  These lamp sockets are NOT available separately from Lectric Limited.  You will need to purchase them separately from an electronic supplier or find a used harness to cut/splice them from.

SWITCHES & RELAYS
Switches: No changes are necessary as most switches can easily handle a 12V system.

Relays (if applicable): When converting from a 6V to 12V system, relays are not cut & dry.  The issue is within the coil component of the relay, not the switching (contact) part.  Some 6V relays will work just fine with 12V applied.  Some may burn-out immediately.  Some may last if 12V is only applied for a short period of time.  Some may work fine but the coil will heat-up more than normal (which may lead to premature failure). If money was no object, replace all the relays with ones rated for a 12V application. If you are on a  budget and want to tell if your particular 6V relay is OK to leave in or if it needs to be replaced by a comparable 12V unit, that would be for you to decide.

MISC:
Radio: This must be replaced by a 12V unit or converted for use with 12V by a qualified radio serviceman.

Dash Clock: This must be replaced by a 12V unit.

Horn: This must be replaced by a 12V unit.

Turn Signal Flasher: This must be replaced by a comparable 12V flasher.

Windshield Wiper Motor: A 6V wiper motor may be fine if you apply 12V for a short period of time.  However, over prolonged use it can burn-out.  Wiper speed is another issue.  If your wiper speed is not controlled by the wiper motor's windings but rather current to the motor, you may need to add a resistor to the feed wire.  What value resistor?  We don't know.

Grounds: As the old saying goes, "Check your grounds!"  You can never have enough of them. Make SURE the integrity of your ground cables, ground wires, and ground straps, are excellent.  Make sure you have adequate grounds to the body, frame, firewall, instrument cluster, engine, truck bed (if applicable), etc.  If you are unsure whether or not you have sufficient ground, add more.  Corroded terminals or wire, loose terminals or poor connections, frayed wire, etc. will cause problems.

These are the systems (there may be others) that you should address before you decide to convert from a 6V to a 12V electrical system.  As stated earlier, once you have addresses all these systems, you can determine if it is worth your time, effort and expense to make the conversion.  Good luck!

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