In Reply to: 1943 Ford 9N posted by Don Kearfott on July 13, 2022 at 11:05:02:
The FORD 9N-12250 Ballast Resistor will get hot but not red hot as stated. I suggest you get out your wiring manuals and go thru the entire wiring system again with battery disconnected. Are you set up with the OEM 6V/POS GRN system or have you switched out to 12V/NEG GRN? Either way, you need the Ballast Resistor in the circuit. If a 12V system, is your coil 6V or 12V? A 12V setup with a 6V coil requires adding an external 1-OHM resistor to the coil wire inline. Rebuilding the front mount distributor correctly is very important. Rebuilding, setting timing, testing before and after you mount on engine are all SOP. See ‘75Tips for N-Owners’ by Bruce(VA). Follow instructions in OEM Manuals and instructions in our HOW-TO’s forum here. Whichever system you use, your GEN or ALT must use a fan belt tensioning bracket. OEM 2N-10000 GEN came with an attached device; the 9N-10000-C GEN offered a bracket later only for the last 9N unit as shown in picture. You can get free downloadable OEM MPC copies in our MANUALS forum and downloadable copies of WIRING PICTOGRAMS by JMOR in our HOW-TO’s forum.
OEM FORD N-TRACTOR 9N-12250 BALLAST RESISTOR; USED ON FRONT MOUNT DISTRIBUTORS ONLY:
JMOR’S WIRING PICTOGRAMS; EARLY & LATE 9N:
FORD 9N TRACTOR WIRING, AFTER S/N 12500:
FORD 9N-10000-C GENERATOR w/BELT TENSIONING DEVICE: