VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Starting with 12Volt on 6 Volt system

Hi Guys,

I read in Sid Carey's restoration project on 1931Chevrolet site.
I Quote (thanks Sid if I may): "Two days ago, I tried starting the engine several times with the 6 volt battery, but since the engine was stiff from all the new parts, it turned it over too slowly. I hooked up a 12 volt battery, and it turned over much better, but did not start. I then noticed a puddle of oil on the floor, and realized that the hole for the oil pressure gauge feeder tube needed to be plugged. So I temporarily installed the gauge and copper tube. When I turned it over the next time, I noticed it showed 5 lbs. of pressure just turning it over with 12 volts to the starter. Today I squirted starter fluid in the carburetor, wired the choke closed, wired the throttle paritally open, turned it over with 12 volts, and it started quickly! It ran for a few seconds, and died. I restarted it, and it ran smoothly! I cut if off after about 15 secondes, because I had not put any water in it yet. Later, I re-installed the 6 volt battery, and it started and ran great! I cut it off a few seconds later. I'll put water in the radiator when I receive the correct hose clamps in the next few days."

My Q is, I'm waiting for my 6V battery but can I temporally start her with a 12V battery?
Will I damage something on the 6V system?

Thanks Guys, I also will joint the club soon (thanks Forest!)

12 volts to the 6 volt starter, for just a few sedconeds, won't cause the starter to grenade. in the 60's i ran a 6 volt starter on a 12 volt system for months before the 6 volt starter eventually went south. in your case, as soon as the engine starts, remove the 12 volt battery as the coil,points and condensor won't appreciate the 12 volts for an extended period of time. mike

I'm not sure that the dash gauges can take the increased current.
Also I'd be very careful if you ever try to jump start a 6 volt battery with a 12 volt, I had a 6 volt battery explode.

Karl is so correct-if connecting to 6 volt battery with 12 volt how much do you enjoy having eyesight-they will explode-if 6 volt battery is not in equation you are still putting 12 volts to many parts designed for 6 volt-if only applying to ignition use resistor

the knowledge you will gain by becoming a member will prove invaluable as you won't have to reinvent the wheel

When I started my '31 with 12 volts, It was hot-wired. There were no gauges connected and no 6 volt battery connected. The points don't care whether it's 6 or 12 volts and neither does the condenser. The coil can stand it for a short time. I have a '32 "non-chevy" car that runs on 12 volts all the time. Its coil and gauges are 12 volts. It has a 6 volt starter that has never been re-wired for 12 volts and is still doing great after 20 years and 10,000 miles. I guess I've been lucky; I have jump started a few 6 volt cars with 12 volts in the last 35 years. I think next time I'll put on goggles just in case!
Sid

Thanks!

Guess Ill rather wait for my 6V and see, before I cant see with exploded battery

If it were me i'd really wait ti'll you get the correct battery. Short jolts of a 12 volt on a 6 volt system may not hurt NOW, but eventually that all adds up to shortening the life of a component and if it's a crucial component like a starter, your talking some big dallors to repair or replace it.

Hello,
sorry, I cannot explain it because my english is not enough for that, but:
The starter can take 12 volt for decades without damage! Why?
The starter takes only as much current (ampere) as it needs. To explain it I would need lot of terms and words I dont know, but I work on electric and electronic stuff since I was 13 (now I get 50) and as a backjard amateur mechanic I did convert lot of cars (I guess 6) from 6 to 12 volt and I never did change the starter. The first one converted in 1981 still has the 6 Volt starter and runs every day.
So no worry.
The other stuff like ignition coil and gauges should not get 12 Volt for too much time. But as long you connect the 12 Volt battery just as long as neccesary to run the starter nothing bad will happen. The starter will pull down the battery to something around 9 volt and the coil and gauges may take that. But for sure you should disconnect the 12 volt as soon as possible after starting.

Regards
Stefangermany

The problem with using a 6 volt starter for any extended time with a 12 volt battery is: The coils and solinoids are wired to get the correct WATTAGE (power), which will produce more heat from an six volt starter than with a 12 volt battery you will get twice the wattage from a 12 volt battery.
With the pre 12 volt system Chevrolet, leaving 12 volts on the ignition switch and ampmeter will fry your fuel gage windings, and several other things like bulbs. Even an 8 volt battery in a 6 volt car will suffer some problems with bulb life.

I've been thinking about what I said earlier in this thread, "The points don't care whether it's 6 or 12 volts and neither does the condenser." I still agree that is true based on part numbers being the same for points 1949-1962 and condensers 1935-1969. But I would like to add that an ignition resistor is required in all cases when there is not one inside the coil.

I have used a 12 volt battery on my (bad word coming up) Model T Ford Speedster for the last 20 years. I installed a ballast resistor (Napa Part Echlin ICR-13) in the wire from the ignition switch to the coil. I also changed all the lights to 12 volts.
The only thing that happened to the starter is that it engages to hard and has broken a few bendix springs.
I still run a 6 volt generator but if it ever burns up I will replace it with a 12 volt generator.
On my Chevy I have a 6 volt system and I am very happy with that. 6 volt systems turn over slower but they are reliable.