Re: 6 Volt to 12 Volt Conversion for 1939 Super 8

Posted by HH56 On 2013/2/7 13:24:18

Assuming the battery to be in good shape with plenty of CCA capacity, generally the biggest problem with older 6v car electrical is corrosion in connections - particularly the grounds - and cable size. The battery cables need to be those designed for high amperage 6v use. If factory originals make sure the connections are clean on both ends. If they have been replaced with modern cables typically found in parts stores, then most likely they are way too small.

The starter draws a considerable amperage. In doing so, inadequate battery capacity, small cables, poor connections, etc can't supply the needed current so the starter turns slowly. With the large draw it also pulls down the rest of the electrical so the coil doesn't get enough voltage for a proper spark

I would verify all the above is in excellent condition before considering further action.