Alternator set up

Johnau07

Member
I've got a 1949 John Deere A that has
been converted to a 12 volt system. It
had a 12 volt generator on it and we
want to put an alternator on it. We
need help trying to figure out how to
wire it. The alternator is a Delco Remy
12 volt 1 wire.
 
A 1949 John Deere A would be 12 volts from the factory with positive ground (chassis) so it couldn't have been converted as it is already at 12 volts. If it's still factory, it will have two 6 volt batteries. Someone may have changed it to one 12 volt battery. I know how to wire an alternator but I think John T has a good set of instructions. But I don't know how to get his link.
 
We are new to these tractors and are
trying to piece things together in our
mind. We were thinking that the
alternator would put out more voltage
in the system. But I may be wrong.
 
(quoted from post at 09:46:28 02/05/23) We are new to these tractors and are
trying to piece things together in our
mind. We were thinking that the
alternator would put out more voltage
in the system. But I may be wrong.

Voltage should be in the same range for a 12-volt generator or a 12-volt alternator, the alternator might run a bit higher, but shouldn't be much. The bigger increase will likely be the amperage output of the alternator over the generator's output, assuming you have a standard generator on it.

If the tractor is still positive ground you will either need to purchase a positive ground alternator, or convert it to negative ground to use the more common alternators like the Delco 10SI or 12SI type available most anywhere.

This post was edited by Jim.ME on 02/05/2023 at 05:54 am.
 
Ok, thank you I might consider just
putting the generator bag on. I just
have to figure out if it works.
 

I will recommend you take the generator and the voltage regulator to a shop that can hook them up together and check that both are working properly, together. Make sure they test them using the same ground as your tractor.
 
An alternator would be more dependable than the generator and charge your battery faster. Problem with generators is finding a good regulator that will last and if only used occasionally, they won't keep your battery charged.
 
Curious if you solved the problem you had with it needing choke to run and if so what did you find? As far as your charging system you will find on here that you always have the purist who think changing something from original is total blasphemy. I am surprised there has only been one that chimed in. Bottom line is that unless you are really wrapped up about keeping it original it really makes no difference value wise because so many of these were made. I agree with what Mark-IA posted, however giving the original generator a chance is not the worst thing. However, in the future if it proves unreliable I would not give a second thought to installing the alternator. Just remember that the alternator will require a negative chassis ground. If connected to a positive ground system it will immediately be damaged. Converting your tractor to a negative ground only requires changing connections on the ammeter and the ignition coil. Post back if or when you decide to install an alternator, being a Farmall guy I can find you a diagram to go by. It may be for a Farmall but the wiring is so simple on these older machines that it can easily be interpreted to apply.
 
We will be keeping the alternator. We had the connections right, it was that the coil and condenser is bad.
 
Got tired of fighting my 2010 charging system, rebuilt the generator and replaced the regulator then a few year later it wasn t charging again. I was rewiring anyway so I went to a Delco one wire, haven t had to touch it sense. Read that a one wire may not start charging without an initial rev, never had that problem. I also have a Ford TW-5 that originally came with and alternator but external regulator, someone before me replaced with Delco one wire, fine by me.
 
No, we will keep the alternator on the
tractor for work purposes because it
charges the battery better I learned. I
will still keep the generator if I want
to keep it all original.
 
(quoted from post at 07:52:25 02/06/23) No, we will keep the alternator on the
tractor for work purposes because it
charges the battery better I learned. I
will still keep the generator if I want
to keep it all original.

Do you have the alternator mounted and wired or are you still looking for help wiring it? If you are looking for wiring help you need to tell what you have for an alternator as not all alternators wire the same.
 
We had someone stop by that Works on
tractors like this and he helped with
the alternator and got it figured out.
 
[b:654c4848f0][i:654c4848f0]trying to figure out how to wire it. The alternator is a Delco Remy 12 volt 1 wire[/i:654c4848f0][/b:654c4848f0]

Take a look at the ''farmer tech'' illustration below.

cvphoto146845.jpg


This illustration shows a 2 wire alternator with an ''exciter'' switch.

Pure speculation on my part, but connect the 1 wire to the BAT terminal.

Take a look at the 2 wire alternator with an ''exciter'' switch on ''Old John'' our 48A.

cvphoto146846.jpg


Take a look at the ''exciter'' switch.

cvphoto146847.jpg


Take a look at the ammeter.

cvphoto146848.jpg


Hope this helps.
 

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