I have recently dug up a couple of 20year + old Baby Bee Cox engines from my childhood days. They require a battery to start and although I can remember what they looked like, I cannot remember the voltage or current rating. I have been unable to source a suitable batter in South Africa so am looking to build a voltage regulator which will be powered from a 12 7AH battery. What voltage is required and how much current does it need to deliver ?