6 Volt One Lunger - 12 Volt Battery

[Maxie Herrington]

Hello all. I have a 5 hp Acadia, one lunger make and break engine to repower the, "OH YES". I want to use a 12 volt, deep cycle battery for cabin/running lights etc.,(solar power for recharging), but want to use the same battery for the 6 volt engine, which has a magneto. I understand a resistor is required to reduce the 12 volts to six. Went to a local electronics shop and got a big, long lecture on Ohm's law. Said they need to know how much current the engine draws. Got me!

Any ancient mariners out there with an answer or suggestion? Thanks. Max.

[rkrough]

Maxie the resistor you need you would get from an Auto Parts store. It is aluminum cased about 5/8" wide by 1" long. I got mine at NAPA Autoparts(US). Here is a description from the catalogue:
AC Delco U1745 Voltage Reducer. Reduces 12 volts to 6 volts. 1.5 ohm resistance for 4 amp maximum load. Permits use of regular 6 volt accessories on 12 volt systems. Mounts through 7/16" dia. hole. Includes clamp on bracket."

I use it on an old tractor.

[imported_Steven Bauer]

Good answer! :D

[imported_Conrad]

Maxie- if you really have a magneto, not a coil/distributor system, you don't need to do anything- the magneto generates its own energy independent of an outside source. The true magneto will have some connections, but these are typically only to short it internally so as to shut off the engine. The beauty of this set-up is that, like a diesel, no additional power source is needed once the engine is started.

Now, on many older originally magneto engines, a more conventional automotive type distributor and coil have been added to replace a magneto where parts were hard to find, or more conventional/reliable ignition was desired; if this is the case with your engine, then the above answer is indeed what you need. Good luck!

[paladin]

In that lecture about Ohm's Law (which incidentally is a small bar and very small restaraunt in Pattaya Beach Thailand) they should have told you that the energy consumed by your engine setup would have an equal amount dissipated as heat through the resistor. A more proper way would be to use a DC to DC converter which would save about 85% of that lost energy....