12 volt conversion questions

kevinw8n · Nov 9, 2014

Ok my 52 8n ford has a 12 volt battery installed ( by previous owner). I noticed when removing the coil today it is still a 6 volt coil. Should this have been changed also? The wires run from the negative side of it over to a white resistor block then to the ignition switch. The positive side is going to the distributor. I had a plug out and noticed the spark wasn't exactly all that great. I'm wondering if the 12v battery has over time fried the coil.

Clint S · Nov 9, 2014

The white resister block drops the voltage for the coil.

George2615 · Nov 9, 2014

Shouldn't the wire coming from the ignition sw. then to the white resistor block then to the coil be on the positive and negative go to the distributor? Unless maybe the tractor was positive ground.

Soundguy · Nov 11, 2014

correct. coil polarity should match battery polarity, but it only makes a very very small real world difference.

if spark looks bad, clean and adjsut the points, and make sure the ignition switch and all electrical connections are good. might want to see what thhat resistor is. might be too many ohms... might be not enough and coil or points have suffered.

if the coilis an older dry one, i'd repalce it with a modern oil fileld one.. and do away with t he resistor altogether. a side mount 8n works well with a 16$ napa IC14SB and no resistor. Do the regap and cleanup. may be all it needs, vs new parts.

kevinw8n · Nov 11, 2014

My starter was draging and burnt out so I replaced it and filed the points and reset them. Tractor starts and runs nicely now. I think I will invest in a new coil as this one is a old standard brand 6 volt that looks to have been one here for awhile. The resistor is just one of those white 2 prong ones.

Soundguy · Nov 11, 2014

if you get a new coil.. get rid of the resistor and get a 12v coil like a napa ic14sb.

also.. if you filed the points.. they won't last as long as you have removed the hard coating on them...

kevinw8n · Nov 11, 2014

Soundguy said:
if you get a new coil.. get rid of the resistor and get a 12v coil like a napa ic14sb.

also.. if you filed the points.. they won't last as long as you have removed the hard coating on them...

not to worried about them. I got a new set on hand when these go bad.