I bought a surplus military Humvee this week. Not understanding how these things work apparently I left something on inside of it that drained the battery over night. So I go to jump start it today and it has two batteries (a 24V system instead of the standard 12V system in my 4runner. How the freak am I supposed to jump start that? I tried hooking the cables up to two different batteries and it gives power to some parts on one battery and other parts of the vehicle on the other battery. Neither one had enough jump to try and start it. Any suggestions.