Am I harming my car by using a 12 volt battery in a 6 volt system?

The car is a '36 ford. But when I hook up my 6v it cranks really slow and won't start and kills the battery.
But when I hook up my 12v, it cranks super fast and the car fires right up.
I don't really know if the car is 6v though, it still has a gen, but my other 12v old car has a generator too. The original owner says to start it the negative should be on the 6v and the positive on the 12v but when i do that, nothing happens.
Why and am I causing harm using the 12v?

2009-03-08T07:53:52Z

how do i run it on the 6v and start with the 12?

Anonymous2009-03-08T07:41:10Z

Favorite Answer

i have restored old cars for a long time.yes the 6v system sucks.most have the system converted over to the 12v.but if your just gonna start the car with 12v then have it run on a 6v battery then it should not harm a thing.

Anonymous2009-03-08T07:50:30Z

Nothing happens because you need to join the other 2 terminals together on the 6 volt and the 12 volt and then you have 18 volts to start and she will fly over on the starter.You wont do any harm starting the car like this but once started you should run on 6 volt

Anonymous2009-03-08T07:39:54Z

Test the output on the generator. If it is like 14 volts, it is a 12 volt system. If not it is probably 6. You can convert those easily. Just get a 12 volt generator, and be ready to change out blinker relays, and light bulbs as they go from the extra power. Just replace them with 12 volt parts. You are not causing harm really, just a little extra wear and tear on the electrical system from the extra power.

Mr. T2009-03-08T07:40:24Z

Yes, I'm surprised the ignition system hasn't failed. Maybe the electrical system has been changed to 12V. When driving in the demo derby we used to put 24V to a 12V starter, but only to the starter, not the to the distributor.

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