Why Does My Generator Runs But No Power Produce?

A malfunctioning generator can truly throw a wrench in your daily routine. Imagine being left in the dark, unable to rely on any of your usual electric appliances. It’s a frustrating and inconvenient scenario. If you find yourself in this predicament, you may be questioning why your generator is running…

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A malfunctioning generator can truly throw a wrench in your daily routine. Imagine being left in the dark, unable to rely on any of your usual electric appliances. It’s a frustrating and inconvenient scenario. If you find yourself in this predicament, you may be questioning why your generator is running without producing any power and what can be done to rectify the problem.

Why Does My Generator Runs But No Power Produce?

Don’t fret, this informative guide delves into the intricacies of this problem, providing you with a comprehensive understanding of the causes and solutions. From troubleshooting to repair, everything you need to know about why your generator runs but fails to produce power, can be found here.

The Most Common Reason For No Power Production By Your Generator

When your generator runs but doesn’t produce power, the issue is that it has lost its residual magnetism.

Generation of electricity is a complex process that relies on the manipulation of magnetic fields. Unlike what many people assume, these fields aren’t trapped within the generator, but rather, the generator creates its own magnetic fields by converting a part of the generated power into direct current and passing it through a coil which creates an electromagnet.

Once the generator is in use, it retains a fraction of this magnetic field, known as residual magnetism. This residual magnetism is crucial for the generator to produce power again when it is next used. Without residual magnetism, the generator may be running, but it won’t be able to generate any power or perform its functions.

How to fix a generator that runs but has no power (When Residual Magnetism Is The Issue)

If after investigating, you are convinced that residual magnetism is the root cause of your generator’s power generation woes, then you can take matters into your own hands and try any of the various techniques outlined in this article to rectify the problem.

1. 12+ Battery Volt Method

The following things you will need

  • A pair of rubber gloves for protection
  • A light source to illuminate your work area
  • A 12+ Volt battery as a power source

To begin the process of resolving this issue, you’ll need to identify the voltage of your generator. Look for the brush wires, one should be red and the other will be either white or black.

Start by disconnecting both wires, then connect the black or white wire to the generator’s battery ground terminal. Turn on the generator and attach a light source to illuminate your work area.

Next, connect the red brush wire to a 12-volt battery. Press the two brushes against the generator’s terminal for a period of 3 to 5 seconds.

Once completed, carefully remove the battery wire and reattach the brush cable to its corresponding socket. Your generator should now be in working condition.

It’s imperative to keep in mind that the brushes from the automatic voltage generator should be unplugged, as they can cause damage to the generator. Also, it’s important to avoid touching the Automatic Voltage Generator with any other wire as it could result in an electrical shock.

2. An Electric Drill Method

If you’re looking for an easy way to diagnose and potentially fix the residual magnetism problem in your generator, then this method is for you.

To start, connect an electric drill to the generator’s receptacle, making sure that the drill is facing forward. Press the trigger to turn on the drill.

Next, start the generator and release the drill’s trigger. The drill’s chuck should begin to spin in the opposite direction.

This process will reactivate the magnetic field in the generator if residual magnetism is the cause of the issue. The drill will help reform the magnetic field and power the generator.

If the drill fails to spin in the opposite direction, it could be an indication that the reverse switch is not positioned correctly.

Keep in mind, when using this method, it is important to ensure that no attachments are connected to the drill bit as when the generator’s field is reactivated, the drill will turn on automatically and any tools attached to the drill will also begin to spin.

Other Reasons For No Power Production By Your Generator (With Their Fix)

If you have ruled out residual magnetism as the cause of your generator’s power generation issues, then you can explore these other potential reasons for the problem.

Reason #1. Poor Connections

To keep your generator running at its best, it’s crucial to pay attention to the small details. Regularly cleaning and clearing all ports of debris and blockages, and double-checking all connections can help prevent poor connection issues and make your generator as dependable as possible.

Reason #2. Excitation Circuit Wiring Error or Blockage

If you have determined that circuit wiring is the underlying problem with your generator, then it’s essential to take action to correct it. One way to do this is by using a multimeter to pinpoint any blockages in the excitation circuit. If a blockage is identified, you can take steps to remove it by polishing the surface oxide layer, and securing any loose connections that may have caused the problem.

Reason #3. Generator Excitation Winding Broken or Grounded

A broken excitation winding can cause power generation issues in your generator, to detect and fix this problem you can use a 500V ohmmeter to measure the ground insulation of the winding. This will help you find the location of the ground leads. Once you have identified them, you can use a multimeter to pinpoint the broken winding and make the necessary repairs.

Reason #4. Worn Brushes

If you’re experiencing a power generation problem, the brushes of your generator might be the culprit. Replacing them could be an easy and effective way to resolve the issue, giving your generator the new lease of life it needs.

Reason #5. Defective AVR (Automatic Voltage Regulator)

To ensure safety, it’s advisable to unplug the spark plug before proceeding.

Next, remove the alternator cover, which is attached to the generator by bolts or screws. Carefully disconnect the wires connecting the brush assembly to the alternator and take pictures to remember the location of everything.

Then remove the Automatic Voltage Regulator (AVR) from the sleeve, disconnect the quick connector, and connect the new AVR to the quick connector. To finish, reassemble the generator by reversing the steps you took to disassemble it.

Reason #6. Defective Capacitor

To ensure the safety and accuracy of the process, it’s important to first remove the capacitor from the generator and discharge any remaining charge. Using a multimeter, measure the capacitance of the capacitor. The reading should be within +/- 5uf of the labeled value on the capacitor’s side. If it falls outside of this range, it’s necessary to replace the capacitor to ensure efficient power generation.

Reason #7. Defective Breaker

To resolve this issue, it’s important to first unplug the spark plug for safety. Then, remove the screws to disconnect the outlet, paying attention to the wire orientation on the breaker and disconnecting the power harness. Carefully open the outlet housing cover.

Using a flat-head screwdriver, remove the old breaker protective cover. Replace it with the new breaker by snapping it into place. To complete the process, reassemble the outlet by following the steps you took to disassemble it, in reverse order.

Frequently Asked Questions

Why does my generator only produce low voltage?

Voltage drops can be caused by a variety of factors, however, one of the most frequent is an operating load that exceeds the generator’s capability. When this happens, the generator’s performance can suffer, resulting in a slow down or loss of voltage, which in turn can impact the entire system.

How to fix the Generac generator not producing power?

To troubleshoot and fix your Generac portable generator, try the following steps:

First, disconnect all electrical items

Test the generator’s output using an electric appliance

Inspect the breakers and make sure they are not tripped

Start the generator and let it warm up with the choke in the run position and without any electrical items plugged in

Then, connect electrical appliances directly without using an extension cord

Inspect the control panel’s breakers, and reset any tripped breakers

If the generator is still not producing power, determine whether it has a push-button breaker or a switch-style breaker

Push-button breakers can be reset by pressing them back in

Switch-style breakers need to be in the ON position

If the generator still does not produce power, try connecting a drill cord and pulling the trigger.


By understanding the methods outlined above, you now possess the knowledge to fix power generation issues in your generator. The causes of failure in generators can be diverse, but by inspecting the generator, identifying the problem and using the appropriate method, you can restore power and continue your daily routine seamlessly.

I hope this article has been informative and beneficial in shedding light on the reasons for power generation issues in generators. Don’t hesitate to share it with others facing similar problems and leave a comment below if you have any further queries.

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Jennifer Smith

Jennifer Smith, with a rich background marked by a PhD in Electrical Engineering from Stanford University, boasts over 10 years in the power generation sector. Her journey includes a notable 5-year tenure as a Senior Engineer at a reputed energy firm, alongside numerous publications and speaking engagements in industry events, reflecting her deep-rooted expertise in generator design and development.

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