12 Volt Field Coils

[Lorenzo]

I know jack about things electrical. Will a starter with 12 volt field coils operate properly with a 6 volt system?

 

[MikeK]

No. There are two pairs of field coils. A 6V starter has the two pairs in parallel. 12V uses the same coils, but the pairs are in series. You will get significantly less torque from a 12V starter on 6V. It will crank very slow. The other way, a 6V setup on 12V you get near four times (not two) the power. For some, like those with OHV's or very high comp heads, this is way too much torque for the starter gear and bendix spring.

 

[Lorenzo]

Thank you, Mike. I have a notion to go 12 volt soon, and was thinking to rebuild my starter for that and put it to use before the fact. Guess I will use old faithful til then.

 

[Herb Concord Ca]

What Mike K said is true for 12V, the field coils are wired in series.
But if you want to reuse your field coils you need 2 6V starters.
First remove all 8 pole screws, easiest is to drill part way thru and them use a punch to break them. Using the copper button as a reference, the 2 left side coils from both starters are used in one starter and the 2 right side coils from both starters are used in the other starter. You will then have 2 12V starters.