new battery goin dead

Sure, the points being closed will short the battery to ground and kill it.

Wouldn't the coil get quite hot if that were the case?

In any event, if you have a mystery battery drain like that and it isn't obvious, I'd recommend taking off the negative battery cable and put an ohmmeter between the disconnected negative cable and ground. It should read infinity, or very high, or open. If you get something less than 1,000 ohms, start looking for frayed wires, accessories left on, something. (That's for a positive ground system which is original)

If the battery fails and you have over 1,000 ohms, you have a bad battery.
 
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Wouldn't the coil get quite hot if that were the case?

In any event, if you have a mystery battery drain like that and it isn't obvious, I'd recommend taking off the negative battery cable and put an ohmmeter between the disconnected negative cable and ground. It should read infinity, or very high, or open. If you get something less than 1,000 ohms, start looking for frayed wires, accessories left on, something. (That's for a negative ground system which is original)

If the battery fails and you have over 1,000 ohms, you have a bad battery.
I was of the opinion that positive ground was the original.
 
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The only wireing is the ignition. My question is ....can an ignition switch that is left on kill battery

Wouldn't the coil get quite hot if that were the case?

In any event, if you have a mystery battery drain like that and it isn't obvious, I'd recommend taking off the negative battery cable and put an ohmmeter between the disconnected negative cable and ground. It should read infinity, or very high, or open. If you get something less than 1,000 ohms, start looking for frayed wires, accessories left on, something. (That's for a negitive ground system which is original)

If the battery fails and you have over 1,000 ohms, you have a bad battery.

Well first off the OP said the only wiring is the ignition circuit so he shouldn't have to look too far. Second if he does as you suggest and does have a short he will be putting 6 volts directly thru his ohmmeter. Not a good idea.
 
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Well first off the OP said the only wiring is the ignition circuit so he shouldn't have to look too far. Second if he does as you suggest and does have a short he will be putting 6 volts directly thru his ohmmeter. Not a good idea.

No, the battery will be out of the circuit. He should probably have said check the resistance between the removed cable and CHASSIS. I'm sure that's what he meant. Myself, I'd leave the battery in the circuit by putting an ammeter between the removed cable and the battery post.
On another note, draining a battery repeatedly will destroy it. Until the issue is figured out you should remove a battery cable when you park. Also put a trickle charger on the battery for at least a day or two after draining it.
 
No, the battery will be out of the circuit. He should probably have said check the resistance between the removed cable and CHASSIS. I'm sure that's what he meant. Myself, I'd leave the battery in the circuit by putting an ammeter between the removed cable and the battery post.
On another note, draining a battery repeatedly will destroy it. Until the issue is figured out you should remove a battery cable when you park. Also put a trickle charger on the battery for at least a day or two after draining it.
Chassis/ground, same thing. Yes, a sensitive enough ammeter in series would show the amount of mystery drain. Most cars have a fuse at the starter, you could also disconnect that when you leave the car.
 
Wouldn't the coil get quite hot if that were the case?

In any event, if you have a mystery battery drain like that and it isn't obvious, I'd recommend taking off the negative battery cable and put an ohmmeter between the disconnected negative cable and ground. It should read infinity, or very high, or open. If you get something less than 1,000 ohms, start looking for frayed wires, accessories left on, something. (That's for a negative ground system which is original)

If the battery fails and you have over 1,000 ohms, you have a bad battery.
No, the battery will be out of the circuit. He should probably have said check the resistance between the removed cable and CHASSIS. I'm sure that's what he meant. Myself, I'd leave the battery in the circuit by putting an ammeter between the removed cable and the battery post.
On another note, draining a battery repeatedly will destroy it. Until the issue is figured out you should remove a battery cable when you park. Also put a trickle charger on the battery for at least a day or two after draining it.

Yes confusing because at first he said it was negative ground then changed it to positive ground.

Regardless I believe he has his answer, leaving the key on will drain the battery. As he said in the first post
The only wireing is the ignition . My question is ....can an ignition switch that is left on kill battery
 
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To check for the battery draw, it really makes no difference whether the test light is connected between the positive or negative leads. It'll still light the light if the draw is there.

And if the points are closed there will be a draw and the coil will get hot.
 
As a matter of safety I always just pulled the NEG cable off after I shut the Model A down after a drive. And if I was going to let it sit more than a month or so I'd hook up a trickle charger until it was charged and then unhook that.
 
I have found 6V batteries have a shorter life compared with 12V.
Now my 6V has died I have made the decision to convert. I believe it is important to change the starter at the same time otherwise the impact on engagement is far too severe and sooner or later something has to fail.
 
this is a build in progress . the only wires are what is needed to run engine and charge battery. the ampmeter shows a 10amp charge when it runs . battery voltage read 2.75 volts this morning and it has been on a charger since that reading was taken.
 
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