Re: How many amps for a 6V battery?

[David Stanton]

The dry cells won’t work – you will just damage the batteries, but 6 Volt starters work fine on 12 volts and give much faster starts, so the small motorcycle 12s mentioned by others will work, the question is how many starts do you want on a charge? and how long do you want to crank if it doesn’t start right away? like if it gets flooded? Don’t go too small. If you go to 12 volts, I recommend a resistor in series with the choke actuator to drop it to 6 volts, because if it’s held on too long with 12 volts, it will get hot and may self-destruct. The resistor should be the same Resistance as the choke actuator coil, and have a high enough power rating (Minimum Power in watts = 36/R) For a lighter, smaller, battery at a good price, I recommend the 12 Volt garden tractor batteries – Menards often has them on sale.
Note that due to the inductive nature of the starter motor, it will not draw fully twice the current at 12 volts that it does at 6 volts – Ohms law does not apply directly here. Old 6 volt cars are commonly converted to 12 volts without changing the starter.
Dave