Tractor generators are the last survivors of a dying breed of motor tech. They have been replaced with alternators, albeit mostly in cars. While they have similar functions, they operate differently, and when they become faulty, it’s good to know how to test them before calling in a technician.
A malfunctioning tractor is a nightmare for anyone, and many times, the problem could be a faulty generator. So, knowing how to test a generator on a tractor can save you from a lot of trouble.
What Does a Tractor’s Generator Do?
A tractor’s generator works together with its engine to convert combustible fuel into electrical energy, which the tractor needs to run.
When the tractor’s engine is started, it spins the crankshaft connected to the generator. This, in turn, spins the generator’s axle, which is located within its electromagnetic chamber. This process generates an electrical current which the tractor needs to run.
Tests to Troubleshoot a Faulty Tractor Generator
There are a few tests to help figure out what is wrong with a tractor’s generator. The two tests are mentioned below.
1. Functional Armature Test – This test helps to check if the generator’s motor still works.
2. Voltage Output Test – This test helps to check the generator’s voltage output.
How to Test Armature Functionality
This is a basic test to troubleshoot the functionality of your generator’s armature. It’s pretty simple and requires you to have only two pieces of equipment; two jumper cables (one positive and one negative) and your tractor’s battery.
To carry out this test on your tractor, follow these quick and easy steps:
Step 1: Slip off the belt on your generator’s motor. Since this test confirms that the motor still runs, it’s essential to slip off the belt before starting the process.
Step 2: Insert the tractor’s key in the ignition and turn it on but don’t start the tractor’s engine.
Step 3: Locate a good grounding station on your tractor.
Step 4: Connect one end of a positive jumper cable to the positive terminal on the generator and connect the other end to a grounding station.
Step 5: Connect one end of a negative jumper cable to the negative terminal on your tractor’s battery and place the other end on the generator’s armature.
If the motor rolls, it means that your generator’s motor still works. However, this test does not determine if the generator has any voltage output. To determine this, you will need to conduct the second test.
How to Test a Generator’s Voltage Output
A tractor’s generator’s motor can run without producing any voltage. If this is what you suspect, here is an easy way to test your generator’s voltage output.
The only thing you’ll need to carry out this test is a voltmeter. A voltmeter is typically used to measure the electrical voltage produced in a circuit. To carry out this test on your tractor, follow these quick and easy steps:
Step 1: Ensure that your tractor is completely motionless and parked in a safe space.
Step 2: Adjust the voltmeter to the voltage of your tractor. In most cases, 50 or 60 volts are adequate.
Step 3: Put your key in the ignition and turn it on without starting the engine. This is to allow some current to flow into the generator for the voltmeter to detect.
Step 4: Connect the voltmeter’s positive and negative cables to the appropriate terminals on the generator. If the generator has any voltage output, the voltmeter will detect it.
Step 5: Start the tractor’s engine and keep it running for a few minutes. Recheck the voltmeter’s reading for consistency.
If your generator is fully functional, the voltmeter should detect some electrical current and show readings with the engine off or on. If no reading is detected, the most likely reason is worn-out brushes in the generator.
To validate this theory, simply exert a little force on the brushes with the engine still running. If the voltmeter’s reading spikes up, then you know for sure that the generator’s brushes are too worn out to generate sufficient pressure on their own.
All you need to do in this case is to replace the brushes, and you are all good. In some other cases, it might simply be time to replace the entire generator.
Closing Thoughts
Knowing how to test a generator on a tractor can save you a lot of guesswork and money. Before you pay top dollar to repair or replace a tractor’s generator, these tests can help you know what to do completely free of charge.
