I just got a new 6amp 12volt supply, and my little electrolyzer is amazing now. There is a constant stream of bubbles coming out of the bubbler's 1/4 inch line.
sounds like you would really be surprised if you hooked your leads to an idleing car and got 13 to 14 v and 10 to 20 amps.Are your cells flooded or serries?Im assuming they are flooded.