I converted my 51 to 12V using the 6V starter on the Flathead 6. I went out to start it today and it turned over once and the starter died. I had picked up a 12V unit at a swapmeet (not sure what year, or engine) and had it lying in the garage just in case. I pulled the 6V starter and dissembled both units. I took the 6V armature and put it in the 12V housing. The starter works just fine so far although it will need new brushes and the communtator turned before long. If anyone does any starter work be sure to lube the brass bushing in the front cover.

 

Good reminder! More starters and generators fail because of bearings than from wiring issues. Be sure to use a minimal amount of a high quality high temp grease like a lithium or heavy duty wheel bearing grease for disc brake applications. Starters get heat soaked and you don't want the grease melting.