I have an old JD 111 mower that I re-powered with a 12 HP B&S engine about 2 years ago. When I installed the engine I replaced the stator to a higher output one since the mower has an electric PTO. At 3300 rpm it puts out 17.6 volts with the PTO off. With the PTO on I get 15.3 volts. I use this mower mostly for pulling a garden cart. Therefore, most of the time it is outputting 17.6 volts. The mower has a diode to convert AC to DC. This too was replaced when I installed the new engine. I know this high voltage is bad on batteries. What can I do about it? Should I get a regulator? Using my meter set to 30 and AC, it read 0.15 volts with PTO off.