12 volt conversion

Wed May 05, 2004 10:15 am

What's necessary to convert electrical system from 6 volt to 12 volt :?: . And which parts are used, and parts aren't in the conversion :?: Can you jump start the system with a 12 volt battery :?: I'm starting a Cub that hasn't run in over 3 years :!: :( :( :( :( :( :( :( :( :( :( :( :( :(

Wed May 05, 2004 10:26 am

Larry, basically you'll need a 12 volt generator / voltage regulator or an alternator. Also a ballast resistor for the ignition coil plus 12 volt light bulbs for the lights. You can keep the 6 volt starter. Just remember not to crank the engine for long periods. If you use an alternator, you will need a load to excite the alternator - usually a small light bulb. You might want to view some of the conversion diagrams at the link:


Wed May 05, 2004 11:36 am


To add what BigDog said, go to the manual server and under Maintenance Tips and Techniques is JD's article 12 Volt Conversion with a Hitachi 14231 Alternator.

Complete guide to conversion.

My question as usual is why? 6 volt system works great. Or is it the cost? Are you needing to have the generator, mag or cut-out replaced or rebuilt? As I continue with Jethro's restore, I am changing him back from the 12 volt conversion to the 6 volt original. Yust me dos centavos....

Wed May 05, 2004 5:43 pm

You mentioned a ballast resistor for the six volt coil. Is this just to keep the old coil in place and save $$$? Or, is there a specific reason for leaving the 6V coil? I put a 12V coil on my '49 and did away with the ballast resistor. Been running good. So far!! :lol: 8)

Wed May 05, 2004 6:15 pm

Either way will work. If the existing coil is good, the ballast resistor is a cheap alternative to buying a new 12 volt coil.