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9n generator

bassman All right guys my generator looks like a old 6volt but its putting out around 13.3v. It also has the high/low adjustment screw.I dont know what the heck i have iwas told to just put a 12 v battery in it but its set up for straight 6volt. I just dont know what to do any help would be appreciated.
mark sr Sounds like you have a 12 volt generator. Is it negative ground? Is the coil 6 volt or 12?
Bob G The generator could have been modified to produce 13.3 volts. I would take it to a generator repair shop and find out what you have. no sense in guessing at this point. you either need a generator that puts out the correct voltage or a battery and system to go with what you have.
Jim Loveridge bassman, you said you have gone through 3 batteries since April. How long have you had this tractor?
Ed i would use a volt meter koked right to the generator while on tractor...unhook what wire you have to it right now...connect volt meter..negative to lead from generator & pos to ground,,,if you get a negative readinf of 13 bolkts or even 6 volts then reverse the leads,,can tell it its charging & what its putting out,,,thats all a shop will do to test one anyway,,,good luck
bassman Ive had the tractor for about 5 years. It is negetive ground and coil is 6 volt. I think the only reason i havent burned everything up is the small metal box regulator i think is not allowing any voltage through it.
Jim Loveridge What is puzzling about this is why you are seeing 13 volts at the one wire alt/gen. You should only be getting no more than 7 or 7.5 volts if the generator is a 6 volt. Your 9N didn't have a voltage regulator originaly. It had a cut out relay, a round device mounted on the back of the dash. It sounds to me like your 9N was converted to 12 volts, but the ignition was left at 6 volts which is common. But why you have a 6 volt battery is the mystery. Then also you are correct in thinking that the replacement voltage regulator is at fault, but if it had a 6 volt battery in a 12 volt charging system I don't know what that might have done to the regulator. It might have burned it up.
bassman alright guys i took the generator to a shop and they tested it it was puting out 7 to 7.4 volts if there was voltage present on the one wire if they took the voltage away it jumped up to 13.2 at the terminal i think its all 6 volts and i need a new cut out. What are your thoughts.

Ed i dont think a bew cut out will solve your problem,,,only thing a cut out does is cuts off the cyrrent when tractor shuts down & when started the points close up to send a charge to the voltage reg & thru the not sure byt i dont think it should be putting 13volts at all ...sounds like it shorted out inside the armature,,,,even with the one wire hooked & tested it should read the same,,doesnt make sense to read 7-7.4..should the same at terminal with ot with out the wire hooked,,,bet its a short inside the generator,,,good luck
Bob G what is the small metal box regulator you spoke of? and if it is 6 volts then the positive post should go to ground. Something about the whole setup is fishy. I would get a wiring diagragm for a 9n, google search, and study it and make sure yours is wired the same even if you have to rep;lace the wiring harness and cutout. if may be that someone removed the cutout and installed a voltage regulator. I don't know enough about the generator to know what is going on but the shop that tested it should be able to tell you what is happening. if they can't I would find adifferent shop. The FO-4 service manual has good section on generators. If you don't have one I would invest in one. Most tractor places should ahve it or get it online. Yours SHOULD be a three brush type with no voltage regulator, just the cutout.
Jim Loveridge It's a bad cutout relay. The contacts inside aren't closing anymore. That's why you see the high voltage at the generator.
Ed thought he stated he had it tested at a "shop" without any cutout...just with the one wire hooked to the generator...i have by passed the cut out & still only got a 7 -7.4 reading at the battery...and their shouldnt be a voltage regulator as stated,,,bob is right,,,something fishy about the entire set up..maybe its just me
bassman it is a positive ground and they let me look at there testing in the shop if gen had voltage at terminal it was 7-7.4 without it was around 13do you think i should make it a pos ground at battery or leave it neg either way im gettin a new cutout or will try to smack old one first iread somewhere they like to stick
bassman sorry i mispoke it is neg ground and was just wondering do i need a cutout or will a vltage regulator work what i have is not round but rectangular
Bob G John deere has a rectangular cutout. after this many years you could have just about anything. a voltage regulator will not work right on a three brush generator. Like i said before set it up like it was when new. set it up positive post on battery to ground. when all hooked up with new round cutout wired like the diagragms show and before running polarize the generator by jumping between the two terminals on the cutout with the ignition switch off. this is to get the generator and battery set up for the same polarity.
bassman will try if i can find a cut out this weekend and repost with results thanks to all who have helped so far
bassman well im finaly getting somewhere I can consistently get 7.3 volts at generator terminal and at gen side of cutout on the battery side i only get 6.4 to 6.7.I can see the volts on my meter go up when the engine is reved.amp meter is showing +4 with lights off and -4 with lights on.I was hoping to see at least a 7v at the battery. I was wondering about wire size from gen to cut out and from cut out to ampmeter I changed both wires to 10 ga. what are your thoughts and also a big thanks to all on the forum who have helped.
Ed what did you finally determine what was wrong??..the 10 ga wire size should work just fine..have you tried screwing the adjuster on the sinde of generator to see if it helped any..who drives a tractor at night aymore anyway,,LOL,,,if its charging ok like it is & your battery stays up,,,i wouldnt mess with it anymore untill really needs fixed..
Bob G I would clean ALL of the battry cable ends. corroaded connections will cause resisance. Also all terminial from the generator thru cutout and on to battery. remove and clean them all. then ssee what you get.
bassman well i found a wire coming off of ampmeter bad it was burned up, as well as the amp meter was bad i guess it shoted out or something i just happened to have a spare laying around and replaced it. i put the battery back to pos grnd and polarized the gen with the small wire between post on cutout. replaced a few wires with new mainly between gen and cut out and cutout to ampmeter and ampmeter ti ignition switch. I was wondering if i need the small resistor that was factory on the tractor.
Bob G You need the ballast resistor that should be in the ingition circuit. without it you will burn up the coil.
bob g
Re: 9n generator

see wiring diagram. resistor is part of the terminal block.

Bob G
Re: 9n generator

maybe this one is better

Bob G Someting is not working right for me. If you need the wiring daigragm do a google search for 9n wiring diagram. you will find what you need.
bassman as for as the ballast resistor the tractor doesnt have one but i do have a spare original on the shelf. should i just do an ohm check on it and what readings would i expect to see.
Bob G The orginial ballast resistor varies resistance according to how hot it is. The hotter the resistor the higher the resistance. So if it shows resistance and is not open it should work just fine. I would install it according to the wiring diagram and then check your spark.
Bob D I too have a 9 N with a cutout in lieu of a regulator. Does the cutout switch jusy cutout above 6 or 7 volts and close when the battery voltage is below 6? I'm suspecting a bad cutout on mine because the generator puts out fine when the wire to the tractor is disconnected. Any ideas?

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