question Whats involved with converting a vehicle from 6 volt to 12 volt?

[LarryH57]

Out of interest what's involved with converting a vehicle from 6 volt to 12 volt and why bother?

 

Presumably 12v gives better starting and lights. Is the job complicated or is there an easy way?

[Pete Ashby]

Change the bulbs, dynamo, CVC box ( these need to be paired up so that output equals control ability) buy a new battery, coil and that's about it.

 

Why do it ?.... no need...... if all the earths are good, battery cables are of the correct gauge and the electrical equipment is in spec and the engine is timed correctly and in good condition and the battery is large enough for the job.

 

It's a personal choice at the end of the day. Iv'e done it in the past if asked to, converting to 12 volt will give faster cranking speeds and perceived better starting, however it can mask any or all of the above issues until the units ultimately fail

 

Pete

Edited January 5, 2015 by Pete Ashby

[teletech]

If your vehicle needs to be really original and you want the authentically frustrating experience then keep it 6V, if you actually need to drive it without much fuss and are willing to do the work up front I really advocate the conversion, there is a reason everybody changed! I had a 1953 dodge for many years and had to replace the 6V battery every couple years and even then getting it started on a cold winter morning was a chore, after I converted it it started right up in the worst conditions.

 

with 12 volt you get much better cold starting as lead-acid battery chemistry has a large voltage sag when cold, and more tolerant of voltage drop from a slightly loose or corroded cable and your battery can be a bit old and weak and still be OK. It allows you to use an in-distributor electronic ignition as opposed to points which results in better reliability and lower maintenance. You can buy batteries and (brighter) bulbs anywhere and also should you need a jump or want to help out with one it's easy. You can also power things like your GPS, a car radio, and cellphone which can be handy.

 

Some guys who just need a little more will go with an 8-volt tractor battery and most adjustable regulators can be set up to give the extra charge voltage.

 

the conversion depends on the age of the vehicle and what gear is fitted.

The regulator, all bulbs(including headlamps,markers, instrument lamps etc.), the coil and condenser are a start, then you need to consider also the instruments themselves (often an external regulator can be fitted), likely a generator, sometimes a fuel pump (I think all the electric fuel pumps are 12+v but not sure). Technically you need to change/ rewind the starter but most folks I've seen just leave it and it seems to work out. If a heater is fitted, this can be annoying as you need a re-wind, new motor, or somewhat hefty regulator.

 

I think Eastwood and some others have pretty substantial regulators and you can run a split system if you don't want to fuss with your gauges or keep your old, dim brakelights.

 

good luck,

P_

[N.O.S.]

Small capacity resistors are available to instal in the feed to the fuel gauge (+ve feed to resistor to gauge to tank sender unit to earth). Pretty much everything else is a bulb change (plus flasher unit if fitted).

 

What vehicle are you looking at?

[TooTallMike]

I'd recommend taking the opportunity to fit an alternator at the same time. Depending on the vehicle type there are suppliers out there that can supply alternators that looks like old style generators if the appearance is important. Otherwise there is a standard modern alternator out there for pretty much any application.

 

You will encounter a few people who will insist that vehicles ran fine on 6V when they were built, but how many new 6V cars are on the market nowadays? There's a reason for that...

 

You will not regret the conversion!

 

- MG

[Lauren Child]

The higher the voltage, the more energy can be transferred for the amount of current (voltage is like pressure, current is like flow rate). People use higher voltages so the current drops and they can use thinner, cheaper cable, and because the lower current flow causes less energy to be lost as heat (hence electricity pylons running at very high voltages - they need to transfer a lot of energy without overheating or being wasteful).

 

For the vehicles, theres no need to change unless theres something wrong and you cant fix it. Its difficult to find 6volt kit for replacements, and with lower current, 12 volts and 24 volts are more resilient to bad connections / faulty components restricting the flow.

 

Give us some idea of the problem and we'll try and help you fix it instead of converting if you like.

Edited January 5, 2015 by Lauren Child

[tankdriver]

One thing most people do wrong, they go to Autozone and pick up a new battery cable, which is for a 12vt system, and is usually a #2 wire.

 

A 6 vt system needs a LOT larger wire to carry the extra amps needed for the lower voltage. For 6 vt you need at least a 1/0 or a 1/00 wire.

 

This is from a IH tractor I have used for years on a old IH 240 I used to own. Still holds true, and for all 6vt systems....

 

 

"The most frequently asked question is "how to I convert my, tractor to a 12 volt electrical system?". My answer to this question is always "Why?". These tractors were designed to start perfectly well on 6 volts, and will today if you have proper cables and a good battery. The first thing to check is battery cables. The reason manufacturers went to 12 volts is not that it starts better, but that it will work fine with thinner cables which cost less. Many Hs through the years had their cables replaced with thin 12 volt cables. If you have these, you need to throw them away and replace them with big 0 gauge or better cables. Make sure that your ground cable (remember, the H has a positive ground system) goes directly to one of the starter mounting bolts and makes good connections on both ends. Then make sure that the cable from the battery to the starter switch and on to the starter is also good. If your starter switch gets hot when you press it, consider replacing it too. If you have good cables and a good battery, it'll start right up."

[Tony B]

I have both a 12 volt Dodge and a 6 Volt Dodge. Rules are the same for both, keep your earths clean and tight! Fix connections to earth and starter with toothed anti shake washers. Current flows on the surface of a conductor, and as Volts X Amps = Watts a 6 volt requiers double the amps, so ideally double the surface area of the condutor. Both mine have Frank Jolley's electronic igntion units fitted, that has improved them more than anything.

[oily]

All bulbs, as an obvious one, ignition coil, and capacitor in distributor (if petrol), starter motor, Dynamo , Control Box+voltage regulator, or alternator....

 

 

Sent from my iPad using Tapatalk

[fv1609]

Matt you wouldn't need to change the distributor capacitor.

[Ian L]

All bulbs, as an obvious one, ignition coil, and capacitor in distributor (if petrol), starter motor, Dynamo , Control Box+voltage regulator, or alternator....

 

 

Sent from my iPad using Tapatalk

 

Capacitor in the distributor is the same for 6v & 12v

[Gordon_M]

I've not done it myself so have no first hand knowledge, but I do hear good things about fitting an eight volt battery

( Optima? ) and making a minor adjustment to the voltage regulator output to put the required voltage into it.

 

Apparently this makes a very noticeable improvement to starting, and the voltage regulator is the only thing you have to adjust, everything else stays the same.

 

I do agree with the advice that if you are running 6 volts you cannot afford and dirty or slack connections. I fitted a battery disconnect to my DUKW and then took it out again when I detected that there was a 0.5 volt drop across it in the circuit, which is too much to lose on a 6 volt system.