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Subject: 6 volt positive ground?

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James Mort    Posted 05-16-2018 at 14:28:08 [URL] [DELETE]        [Reply] [Email]  
  • 6 volt positive ground?
  • Iím new to this, is this tractor 6 volt positive ground? Serial number on the block is 9N105085, it has a generator. The PO had a 12 volt battery in it hooked up to negative ground. I started it by jumping straight to the starter. It took right off and ran but I want to make it original. The POís son told me the battery was always dead.

    James Mort    Posted 05-17-2018 at 06:41:03 [URL] [DELETE]        [Reply] [Email]  
  • Re: 6 volt positive ground?
  • Thanks for the help. By new to this I meant N tractors, I used to have a 50 Plymouth so some of the 6 volt positive ground stuff is familiar. The generator does have the high/low adjustment on the back, but I didnít know about polarizing it. I did start it by jumping it correctly with the 12 volt battery (after checking the oil, radiator juice and making sure it was in neutral) and it popped right off and idled good. I need to get it to my house as the POís widow and son want it gone. This weekend Iím going to the farm store and buying the correct 6 volt battery. It has an old loader on it that makes getting to the engine difficult so Iíll have to get that blocked in the up position or removed. I will get manuals and pictographs, those are very helpful. Thanks for everyoneís quick feedback, it really helps.

    Bruce (VA)    Posted 05-17-2018 at 10:00:10 [URL] [DELETE]        [Reply] [Email]  
  • Re: 6 volt positive ground?
  • The original 6V battery is Group Size 1 - 9-1/8 (L) x 7-1/8 (W) x 9-3/8 (H).

    12V Group 25 & Group 35 batteries are just slightly smaller at 9-1/16 x
    6-7/8 x 8-7/8.

    Tim Daley(MI)    Posted 05-17-2018 at 07:22:35 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • We already mentioned getting the WIRING PICTOGRAMS by JMOR document downloaded and use it as a valuable tool. Be aware that trying to save $$$ and buying the bargain-house brand batteries can be an unwise choice. Off-brands usually only last about two years and some can be junk out the door. Get a good brand like INTERTSTATE, DEKA, or EXIDE, a GP-1 AG type and no DEEP CYCLE type. Average cost of a good brand is about $125 but well worth the investment and can expect at least 5 years life out of it. Your trusty starter shop usually carries the decent brands and you can get the core charge lifted by trading in your old battery. Also invest the proper battery cables. Then verify the rets of the wiring is correct too. I don't see how you are getting it to stay running by jumping it. there's more to it than just putting a new battery in as stated already. The FEL won't interfere with installing a new battery but can inhibit getting to the distributor. While battery is disconnected or removed, diagnose all the wiring. Generator uses a cutout. Starter shop can bench test all your electrical parts too. In my document on early 9N/2N generator article I detail the correct way to polarize the generator with a cutout. Get all the wiring right BEFORE connecting the battery. Polarizing will be the LAST step done BEFORE applying power with the key switch/starter button. I'm jumping ahead here a bit, but once you get your new tractor running properly, you might want to invest in a float charger aka a Battery Tender and leave it connected when tractor is not in use. It will preserve the life of the battery and keep it a full charge so it's ready to use when you are. here's a LINK to an old post by Bruce(VA) on why using a float charger is beneficial.

    Tim Daley(MI)

    K.LaRue-VA    Posted 05-16-2018 at 16:53:13 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • The original system was 6 volt positive ground. The 12 volt battery is always dead because a 6 volt system will not charge a 12 volt battery.

    Making it original and reliable will require a 6 volt battery, probably a voltage regulator, and completely going thru the electrical system. I would rework, or replace the wiring harness, shine every terminal screw connection point, replace terminal hardware with new zinc-plated nuts. Look at battery cables. Toss them if they are the skinny automotive type. Replace with the proper heavy gauge tractor battery cable and ground strap. Some references list #2 gauge for the tractor battery cable. I use 1/0 or 2/0 welding cable, with brass solder terminal ends.

    Tim Daley(MI)    Posted 05-17-2018 at 04:57:03 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • HiYa Kebby-
    Yes, battery cables are part of the wiring and both are so important to the electrical system, yet often overlooked. I have and always will say that non-running/non-starting issues with these old N's is 99.98% due to some sort of cobbled up 12-volt switchover job. The daily posts on the tractor boards are proof alone. To avoid confusion, I will add that only the first 9N-10000-A generator used a voltage regulator, then obsolete with the 9N-10000-B unit, as the round-can cutout circuit was released. The round-can cutout was used up through 2N production, then with the 8N model released in July, 1947, a new generator and voltage regulator were used. A VR can be used on a 9N or 2N IF the generator has been changed to an 8N unit. Otherwise a 9N-B and/or a 2N generator must use the round-can cutout in order to function properly. I have worked on several wrong non-starting configurations, including tractors with 12V batteries plus the cutout and sometimes a VR connected as well. I've had 6V 8N's with correct generator yet a cutout installed and no VR. I've had and have seen many N-Series models using Model A car generators. These are obvious as the round-can cutout is mounted on top of the generator. I also have seen tractors with early V8 generators -wrong on various levels, one being the output could be up to 85 amps. 9N/2N gennys should only be 7-11.5 amps. When Ford engineers designed the 9N tractor, it was all relatively new. they originally tried a Model A type genny with cutout then determined that the tractor needed a more robust, sealed unit as it was exposed to the elements greater than a car set up. There is a photo in most of the Ford tractor books of a prototype 9N tractor with a Model A generator mounted on it. For some reason or other it was determined the new tractor needed its own generator with a voltage regulator. I still find this as an odd decision because we all know Ford was a frugal man and demanded that parts already in the pipeline be used across the board in multiple modules. The round-can cutout was one of those parts. It's ironic that they soon, by early 1940, discarded the 9N-A genny using a voltage regulator and opted to go with the cutout circuit. There were severe charging problems with the early generators. Changes were made fast and furious to correct that -i.e. switching to a cutout, using different size pulleys, etc. when part of the true root cause was those early units had no tensioning device to keep the fan belt tight and the genny charging. There was only the mounting/pivot bolt on the units which, under load, would loosen up on their own and thus cause the non-charging issues. Ask any old timer how many times they were stranded in a field at the end of the day or sooner because their tractor battery was dead. It took Ford engineers a few years to realize this and thus came up with a belt tensioning device to keep the fan belt solidly secure. The device was standard on the new 2N-10000 generator and a kit was available from the dealer to install on the previous 9N-10000-C generator. The 9N-C and 2N gennys were virtually the same except for this part. The device will not work on the earlier 9N-A and 9N-B gennys as they have smaller barrel diameters. Some farmers realized the problem before Ford did and came up with own tensioning devices too. The later 8N generators, 1947-1949, on tractors with the front mount distributors, used a totally different tensioning arm, P/N 8N-10145. I often see this part missing on 8N generators too. Anyway, here's a LINK to my article on the early 9N/2N generators. It is so important that one understands the why's and how's of the electrical systems on these Ns. Simply swapping out the original 6-volt battery with a 12-volt battery does not now make it a 12-volt set up.

    Tim Daley(MI)

    Tim Daley(MI)    Posted 05-16-2018 at 16:25:59 [URL] [DELETE]        [Reply] [Email]  
  • Re: 6 volt positive ground?
  • HiYa James-
    First, welcome aboard! You won't find any other place on earth with more useful, often original information on these old Ford Tractors and staffed with many helpful members. No dues or fees required but you can find a ton useful documents and manuals in our library of DVDs and such for a modest donation. We have a MANUALS forum where you can download a lot of original Ford-Ferguson and Dearborn manuals that have been scanned plus many useful documents in our HOW-RO's forum as well.

    Now, to answer your questions, we cannot tell you if your tractor is 6 or 12 volts simply by a serial number. The original FORD electrical systems were 6-volt/positive ground. Many have been switched over to 12 volts, but bear in mind simply swapping out the battery from a 6 to a 12 volt unit does NOT define it as a 12volt system either. Also noteworthy to is that many 12-volt "conversion" jobs are not done correctly. You say you have a 12-volt battery AND the generator is still in place. Well, unless the generator is 12-volts, this is proof you probably have a hacked-up job too. !2 volt jobs usually use an alternator and are connected as a negative ground system -like your modern car. Then that still isn't what makes a 12-vol job right and complete. See WIRING PICTOGRAMS by JMOR in our HOW-TO's/Electrical forum. If your s/n is indeed *9N105085* then that indicates it is a 1942 9N, possibly late, and possibly a wartime 2N, meaning steel wheels and magneto and such. More later on that. As a new N-Owner, you should get copies or originals of the essential manuals required. The I&T F-04 Manual and a copy of the '39-'53 MPC (Master Parts Catalogue) are mandatory. The others are original 9N and 2N Service and Owner/Operator's manuals. We have some of these here in our MANUALS forum for free download. Here is a LINK to John Smiths' old page on ID-ing these old Ford Tractors better. Also, suggest you download the WIRING PICTOGRAMS and a copy of Bruce(VA)'s 75 Tips for N-Owners in our library as well. There is also a document of a checklist of the things to do BEFORE firing up a newly purchased tractor. You are going to want to go thru the list methodically before trying to run it and first order up getting the electrical system figured out and corrected. You say you want to keep it all original. That's fine, many of us run our N's on the original 6-volt positive ground systems with NO PROBLEMS. There's nothing wrong with wanting a more modern 12-volt system, but either way, the setup MUST BE wired correctly in order to function well. The 6-volt/positive ground setup on the 9N/2N uses a 6-volt battery, positively grounded; a generator; a starter; and a round-can cutout circuit. It will have a coil on top of the front mounted distributor - something else we will get into as we go -a keys witch and an ammeter. Lighting kits were optional so you may or may not have those, but we'll also deal with lights later. 9N/2N 12-volt conversion jobs use a 12-volt/negative grounded battery; an alternator -can be 1-wire or 3-wire; the ammeter or a voltmeter; key switch, and either the 6-volt coil or a newer 12-volt coil. If 6-volts, you will need to add an external in-line resistor to the wiring. Either way, 6-volt or 12-volt, you MUST use the original ballast resistor mounted to the back of dash near the ammeter. You can take the battery, generator, starter, coil, ammeter, cutout, and key switch to your trusty local starter/alternator shop guy who knows old Fords and get them all tested. the first crucial piece to test will be the battery. Whether 6 or 12 volts, invest in a good brand like INTERSTATE, DEKA, or EXIDE. Bargain-house batteries sold at most auto parts stores and off-shoot hardware stores usually have poor lifespans -like 2 years max. get started right with these basics and we will nurse you along. My email is open too. Good luck!


    Tim Daley(MI)

    Bruce (VA)    Posted 05-16-2018 at 16:23:58 [URL] [DELETE]        [Reply] [Email]  
  • Re: 6 volt positive ground?
  • Well, if it has a 6v generator and a 12v battery, it's pretty obvious why the battery was always dead.

    Look at the back of the generator; the 9 & 2N generators had an output adjustment screw. Does yours have one?

    If it does, it's 6v for sure.

    Tractor came from the factory 6v positive ground. Put a 6v battery in it & polarize the generator before you start the tractor.

    See tips 23 & 51.

    And tip # 39.

    steveVa    Posted 05-16-2018 at 15:35:43 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • Does it have an alternator or a generator?

    Tony C    Posted 05-17-2018 at 08:33:24 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • NAPA group 4 Commercial battery. $110.00. plenty of CCA ande reserve. Vibration resistant.

    Tim Daley(MI)    Posted 05-18-2018 at 07:39:08 [URL] [DELETE]        [Reply] [No Email]  
  • Re: 6 volt positive ground?
  • GRP-4 data shows length at 12-3/4" -may be too long to fit in an N battery tray. My INTERSTATE (1-VHD) GP-1 6-V battery fits perfect on my 8N tray. I have the original battery cover and hold downs installed as well. GRp-4 dies have more CCW (1000) and CA (1250) but the GP-1 type is spec'd at 640 CCW and 800 CA -a sufficient power source. I've been using these for years and never had any major issues even in cold weather. Plus I now use a Battery Tender when not in use. Just a satisfied Interstate customer. I'm sure there are better ones and I may try a NAPA or DEKA or EXIDE next time, but won't need to replace my 8N battery for many years yet. The next battery I buy will be a replica unit that has the FORD script logo on it for my early 9N project.

    Tim Daley(MI)

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