How To Wire A 3-wire Alternator On A Tractor? 9 Easy Steps

How To Wire A 3-wire Alternator On A Tractor 9 Easy Steps

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If you’re a farmer then you certainly know how important it is to have a tractor and to maintain it on a regular basis. A good working tractor machine can help you a lot when it comes to the task concerning the crops and other things on your farm. That is why it is so important to know how to maintain your tractor or even better, how to improve it so that you can work faster and more efficiently.

For example, one of the easiest and best improvements that you can do to your older tractor machine is to replace the original generator with an alternator. The great thing about alternators is that they do a much better job at charging a battery at the low-speed tractor engines are usually operated.

That is why it is recommendable to replace the existing generator in your older tractor with a 3-wire  alternator. This is not a very complicated task, but you do have to know some basics. In the following steps, you can find out everything there is on how to wire a 3-wire alternator on a tractor. Follow these steps and the improvement to your tractor will be done in just a few simple steps!

Why Do You Need To Choose A 3-wire Alternator? 

What is important to mention about the 3-wire alternator unit is that it can provide your tractor with better electrical performance for your demands on the farm. To explain how the 3-wire alternator works, there are the main charge wire, the exciter wire, and a third wire that can jump between the regulator and the battery stud.

One must mention that the 3-wire system is actually less intrusive than it sounds, as there are only two extra wires integrated into the rest of the electrical system. It is recommendable to choose the 3-wire alternator to improve your tractor unless you are prepared to strictly manage your electrical budget very tightly when cruising at low RPM.

How To Wire A 3-way Alternator On A Tractor?

How To Wire A 3-wire Alternator On A Tractor 9 Easy Steps

In the following steps, you can see how simple it is to wire your new 3-wire alternator to upgrade your old tractor. Follow them, and you will be done in no time!

1. Disconnect The Negative Terminal From The Tractor Battery

Before you start anything, you should disconnect the negative terminal from the tractor battery. This is not a very hard task to do. Nevertheless, you should take caution when doing anything that has to do with electricity or the tractor battery as well.

2. Fabricate Mounting Brackets For The Alternator

This second step might be the hardest part of your new project. But not to worry, anything can be done when you know how to do it right. One must mention that you may also be able to find brackets in a junkyard that will work with minor modifications that can save you extra money, which is a great thing.

Another great thing is that you can make the brackets yourself using ¼-inch flat stock steel that is about 1 inch wide if you cannot find them in a junkyard. This is another great way to save some money, and to improve your old tractor at the same time! 

The next step would be to mount the brackets using the original mounting holes in the engine block for the generator bracket. It is important to mention that you should make certain the pulleys align properly for the belt and that the bracket allows for adjustment of the drive belt. Then, you can install the alternator and the new drive belt.

3. Connect The Output Bolt To The Positive Terminal Of The Battery

You are almost done and you have already done the hardest part! The next step to the improvement of your old tractor is to connect the output bolt on the back of the alternator to the positive terminal of the battery using 10-gauge wire, to which solderless ring terminals have been installed. It is good to mention that you can also make this connection on the starter solenoid where the positive cable is connected. Then, follow the positive cable from the battery to where it is attached which will be the starter solenoid.

4. Connect The Battery Negative Cable

How To Wire A 3-wire Alternator On A Tractor 9 Easy Steps

The last step to improving your old tractor with a 3-wire alternator is to connect the battery negative cable. After this step, you can turn on your tractor and start working on the farm faster and more efficiently which is a great thing for any farmer. By attaching a 3-wire alternator to your old tractor you get better performance, and you get to save money as well!

To give a proper example of how to wire a 3-wire alternator to your old tractor, check out this step-by-step guide on how to wire an AC Delco 3-wire alternator. The AC Delco 3-wire alternator is used in most General Motors products, as well as in many types of heavy equipment. The great thing about this 3-wire alternator is that it offers you the advantages of high output, compact design, and easy use. Using proper brackets, this alternator can be adapted to any vehicle or engine-powered equipment in just a few simple steps. You won’t be needing any special skills to wire this alternator, as it is well within the capabilities of anyone with average mechanical skills.

5. Disconnect The Battery Negative Terminal

As I mentioned in the previous step-by-step guide, the first thing to do when wiring a 3-way alternator to your old tractor is to disconnect the battery negative terminal. This step is very important and must not be avoided.

6. Connect The Wire To The Output Stud

The next step would be to connect a length of 10-gauge wire to the output stud on the back of the alternator using a solderless ring connector. Next, you should connect the opposite end of this wire to the starter solenoid. You can simply connect it to the same terminal as the positive battery cable in just a few simple steps.

7. Plug The Alternator Connector In The Receptacle On The Alternator

The next thing to do is to plug your new alternator connector in the receptacle on the alternator. You should splice a 14-gauge wire to the smaller pigtail from the connector which isn’t very hard to do. This wire runs to the IGN terminal of the ignition switch. The last thing to do in this step is to connect a small 12-volt warning light in series in this wire.

8. Splice A 10-gauge Wire To The Larger Wire On The Alternator Plug

One of the final steps when wiring an AC Delco 3-wire alternator to your tractor is to splice a 10-gauge wire to the larger wire on the alternator plug. For this step, you will need to use a solderless butt connector to make the splice. You should make the wire long enough to connect to the same terminal on the starter solenoid as the battery positive cable and the alternator output wire. Lastly, connect the wire to the terminal with a solderless ring connector. You’re almost done after this step!

9. Finishing Touches

The last step when wiring the AC Delco 3-wire alternator to your old tractor is to finish the job by reconnecting the battery negative terminal. After you’re done with the wiring process, you can use your improved tractor on your farm and work with ease! By replacing the original generator with a 3-wire alternator your tractor will work with more efficiency and will be upgraded to a whole another level. Your improved tractor will enable you to work faster which is the ultimate goal of every farmer out there.

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