400 12 Volt Conversion

Wilks54 · May 16, 2013

I am looking to convert over the 400 from 6V to 12V. I have looked at the Bob M diagrams for the Super M, which should be the same one's I use for the 400, correct? Is there anything or better parts that I should use for the conversion? Specifically, I am wondering-
-Do I need a hotter coil, or just a standard internally regulated one?
-What is the diode for, and do I need that for the 400 set-up?
- Can I just flip the bracket over for the genny and use it for the alternator? and the Delco 10SI will fit that way, correct?

I know these questions have been answered a bunch of times, but wasnt satisfied with the search button. So, thought I'd ask.

Thanks in advance - Wilks54

Hayfarmer · May 16, 2013

You can use the 6 V coil with a resister ahead of it, or get a 12 volt coil with internal or external resister, diode is to prevent feedback to ignition switch through alternator, otherwise you can't shut engine off, I don't know if you can just flip ge bracket over on 400, that is what I did on my nSMTA and with spacers it worked.

Bob M · May 16, 2013

The stock 6 volt coil will work fine. Simply wire a generic Chrysler style ballast resistor in series with the coil primary and you'll be good.

The diode is to prevent the alternator from backfeeding the coil when you shut off the ignition. Without the diode (or a current-limiting generator warning lamp) you won't be able to shut down the engine by turning off the ignition switch.

Flipping the generator bracket will work for the 10SI. You'll need a bit of threaded rod (or a full threaded bolt) and a few nuts to make a new pivot shaft however.

mkirsch · May 16, 2013

You may also need to do some trimming on the bottom mount of the alternator to get the belt lined up perfectly.

Wilks54 · May 16, 2013

Thanks Guys. I am guessing the "cleanest" install is the 12 volt coil with an internal resistor? ...but not necessarily the cheapest?

Im already going this far, and am thinking less parts/connections are better, correct?

charlieu · May 16, 2013

Check out my website, charliesrepair dot com for wiring diagrams for your 400 tractor. I have 25 different diagrams for different tractors set up with different charging systems, coils, resistors and different types of ignition switches. Click on the wiring diagrams button on the top line. These diagrams should help.

teddy52food · May 16, 2013

I would use the same coil with a resistor and add a resistor by-pass circuit for starting.

Janicholson · May 16, 2013

Contrary to the common thinking there are no resistors in 12 volt coils today. They are just designed to run on 14 to 14.6 volts without burning up. As in because you might have an external sidewalk does not mean that if you don't you must have one in the house. (I am not flaming you, it seems logical to say there is one inside, and there is not.)

Wilks54 · May 17, 2013

(quoted from post at 21:02:59 05/16/13) Contrary to the common thinking there are no resistors in 12 volt coils today. They are just designed to run on 14 to 14.6 volts without burning up. As in because you might have an external sidewalk does not mean that if you don't you must have one in the house. (I am not flaming you, it seems logical to say there is one inside, and there is not.)

Not arguing with you Jim, you have more knowledge about these machines in your toenail clippings than I have in total, but why the heck to they advertise them with internal resistors if there arent any? Seems like I should be able to get one for free then, based upon false advertising and defrauding the customer!

Janicholson · May 17, 2013

I have no idea except that the advertizing department is often cleverly described as removed from engineering. and they believe as I indicated, that there is concrete in the living room. Jim

Wilks54 · May 17, 2013

So, then the desired output is done just through windings or wire size, correct?

Janicholson · May 17, 2013

Yes, both the number of windings, and the use of smaller wire. The same as an electric motor. Jim

Wilks54 · May 17, 2013

Thanks to everyone for the help. you guys with all the years of experience are quite an asset to us newbies. I wish grandpa was still around to help with this sort of thing. Anyways, thanks for your constant input and willingness to help.

hoping to have the 12 volt done and power steering installed by Memorial Day weekend.

400 12 Volt Conversion

Wilks54

Member

Hayfarmer

Well-known Member

Bob M

Well-known Member

mkirsch

Well-known Member

Wilks54

Member

charlieu

Member

teddy52food

Well-known Member

Janicholson

Well-known Member

Wilks54

Member

Janicholson

Well-known Member

Wilks54

Member

Janicholson

Well-known Member

Wilks54

Member

Similar threads