N Board Forum - Expanded Thread Page

Subject: Won't start.

[Back] [Return to Top of Forum]

Daniel Jinkens    Posted 02-17-2019 at 01:26:49 [URL] [DELETE]        [Reply] [Email]  
  • Won't start.
  • I have a slight hiccup, put in new wiring harness that I purchased from Steiner Tractor parts. Got the harness in and put battery in backwards. Purchase new harness, installed now won't start. Was also wondering where wire from pos side of ammeter goes. Ammeter had no writes to it when I got the tractor. Thanks for any advise from a new to me tractor owner.

    Rustyal    Posted 02-17-2019 at 07:04:48 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Won't start.
  • The positive side goes to the switched side of the ignition. Probably a junction with other wires that have no power with the key off.

    Tim Daley(MI)    Posted 02-17-2019 at 05:36:14 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Won't start.
  • Dan –first welcome to the NTC. We need a lot more info to help serve you better though. What model of tractor are you talking about? Front Mount Distributor or Angle Mount? Is it 6V/POS GRN or 12V/NEG GRN??? An ammeter not reading right isn’t your problem but we’ll discuss that in a minute. You say you bought a new harness and then put the battery in backwards. Does that mean you connected it in reverse of what it was before? If still OEM 6V then you would have a generator and voltage regulator, or if an earlier 9N or 2N, a cutout. If you have a GEN/VR and battery polarity got switched, your gen would have to be polarized to match otherwise it ain’t gonna work. If 12V then you should have an alternator and no GEN/VR so polarizing is not done. See LINK below to WIRING PICTOGRAMS by JMOR for your setup and then use it to verify what you have and make corrections, no exceptions. AMMETERS are non-polarized. If OEM Induction (LOOP) style, the wire runs thru the loop. If readings are backwards –shows NEG/DISCHARGE when on, simply reverse the wire direction thru the loop. If you have the aftermarket style ammeter with two studs and screw terminals, then the wire is spliced and one end goes on one terminal post the other wire end on the other terminal post. If when ON readings are reversed, simply flip-flop the wires on the posts. It’s possible you have more incorrect wiring than just the ammeter. Start with getting the battery tested –the power source is a key to any electrical system. Starter shops can bench test it under load. They can test your genny, alternator, VR, ammeter and starter too. Concentrate on the wiring first, power OFF, doing continuity, not with an idiot light tester. Don’t just go by wires colors –todays cheap generic harnesses are not OEM color-coded like the OEM ones unless specified. Since you are a newbie I would suggest you invest in the essential manuals as well. The FO-4 and the 39-53 MPC are a good place to start. The 9N/2N Service Manual is in our MANUALS library as well as some of the original MPC's for free download. Here are the 9N/2N and 8N wiring diagrams. If you have a later 8N, NAA, or Hundred Series, they will use the side mount distributor and are wired differently as they do not use the ballast resistor -we can discuss further if that is the case.





    Tim Daley(MI)

    Daniel Jinkens    Posted 02-17-2019 at 08:32:39 [URL] [DELETE]        [Reply] [Email]  
  • Re: Won't start.
  • My tractor is a 1954 NAA, still runs on 6v pos ground system. When I put the first harness in and fumbled the battery it fried the harness. Hence the second harness.

    Tim Daley(MI)    Posted 02-18-2019 at 05:33:42 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Won't start.
  • Your wiring is mucked up for sure. What did you use for a diagram? Like Jack said, reversing polarity on the battery would not smoke the wiring. You'd have issues with the genny not charging, but that too is no cause to smoke the wiring. Nor is an ammeter wired in reverse. The I&T F-19 manual is for the NAA tractor and a useful tool. JMOR's pictograms are also a very useful tool. The NAA 6V/POS GRN system uses the 20A/ B-Circuit type generator meaning polarizing it is different than polarizing the A-Circuit design and if not done correctly will smoke your VR. This is how the original NAA (Jubilee) & Hundred Series Wiring Setup looks:

    You need the F-19 manual, 39-53 MPC, and JMOR's wiring pictograms to see the technical side of the wiring, meaning where each wire goes. Those manuals will also list the OEM correct wire color codes, but like I said earlier, you can't use colors if using a cheap aftermarket harness and also because colors do not conduct electrons. A continuity test is your best friend. Disconnect the battery and perform one before you smoke another harness. It is possible you may have fried the VR now, but root cause problem solving will determine your issue. You should verify the wiring is all correct before you connect the battery.


    Tim Daley(MI)

    Daniel Jinkens    Posted 02-18-2019 at 08:27:48 [URL] [DELETE]        [Reply] [Email]  
  • Re: Won't start.
  • I want to thank everyone for the advice, yesterday I was able to get it sorted out and running. Now I have to figure out the wires for the lights. Does anyone know which side of three switch is pos or neg. Thanks again.

    Jack - Iowa    Posted 02-17-2019 at 09:20:45 [URL] [DELETE]        [Reply] [Email]  
  • Re: Won't start.
  • You had some other problem than the reversed battery. That alone would not fry the wiring. Tractor should start and run just fine with battery reversed but charging circuit would not work until you re-polarized the generator.

    Tim gave you directions to JMOR's wiring diagrams. You need to carefully check and get it connected correctly. That before worrying about any other problem.

    Good Luck

    [Back] [Return to Top of Forum]