In Reply to: Re: ford 9n posted by David on July 11, 2018 at 14:01:37:
History on the 9N/2N Generator:
The first, early 9N-10000 generator, a 2-Wire/2-Brush, 'B' Circuit design unit, output rating 7 AMPS, used a square voltage regulator, p/n 9N-10505 [A] -see photo. It was mounted on the back of the dash, on the lower steering box. Before the end of 1939, charging issues forced Ford engineers to revamp things and the new 9N-10000-B generator was released in April, 1940, on or about s/n 9N-12500. This was a 1-Wire/3-Brush, 'A' circuit design unit, output rating 7 AMPS. This unit now used the round-can cutout circuit, 9N-10505-B -see photo. The 3rd brush was adjusted by a small black slider button on the back plate. It had simply a "HI-LO" setting, no rheostat type adjusting -see JMOR's photo. Charging issues still persisted and thus yet another revamp was performed. In August, 1940, on or about s/n 9N-18000, the 9N-10000-C generator was released. It was now a larger barrel, larger armature unit, but still a 1-Wire/3-Brush "A' circuit design type only the output rating was at 11.5 AMPS. This unit was used up until 1945. WWII would limit domestic production and thus material restrictions imposed by the US War Board kept precious commodities like copper, zinc, aluminum, iron and steel, amongst others, strictly for war ordinance. On January 15, 1945, the new 2N-10000 generator was released. Ford engineers had finally realized the charging issues were due to no belt tension. Up until now, the generator was simply secured on with a single pivot/mounting bolt. Under load in the field, the generator would loosen itself up and thus unable to charge the battery. Many a farmer would end up stranded at the end of the day if not sooner with a dead battery because of this. The tractor operator would need to stop every few hours to tighten up the generator and belt tension if he wasn't aware of this problem. The 2N-10000 generator was virtually the same as the 9N-10000-C generator except it now came with the belt adjustment device bolted to the barrel. A 2 piece device, the spring loaded part was fastened to the barrel and a second 'L'-shaped bracket with a special nut fastened to two head bolts/studs on the front of the cylinder head -see photo. At the same time, a new kit was offered for attaching the device to the prior 9N-10000-C generator only using a steel band around the barrel. The 2N-10000 generator would be used for the duration of 2N production which ceased by January 1, 1947. On July 7, 1947,teh new 8N Model was released and it now had another generator revamp. It was a 3-Wire/3-Brush, 'A' Circuit design unit, rated at 11.5 AMPS output and now used square voltage regulator mounted on the RH back dash near the Oil Pressure Gauge. Whew! A long post but I hope this clarifies a lot of things for you.
FORD TRACTOR P/N 2N-10181-B GENERATOR BELT ADJUSTMENT KIT:
FORD TRACTOR 2N-10000 GENERATOR w/BELT TENSIONING DEVICE:
FORD 9N-10505-A VOLTAGE REGULATOR –USED ONLY ON EARLY ’39 9Ns UNTIL s/n 9N-12500:
FORD TRACTOR 9N-10505-B CUTOUT UNIT, USED ON ALL AFTER s/n 9N-12500: