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generator not producing power, how to fix it?

In this blog, we will look at the common reasons why generators do not produce power. In addition, we will discuss ways to address this problem.

Table of Contents

Many homes rely on generators as a reliable backup power source during power outages, especially during the colder months, to ensure a comfortable and functional home environment. However, it is not uncommon for generators to fail at critical moments.

A common problem is that the generator is running but unable to power the home. BISON consulted our expert technicians to learn more about how to fix this problem, and they can guide if you find yourself stuck.

In this blog, we will look at the common reasons why generators do not produce power. In addition, we will discuss ways to address this problem.

View more information about generator repairs If your BISON generator fails, we can safely diagnose and fix the problem.

generator not producing power how to fix it

reasons why my generator runs but produces no power, how can I fix it?

You need to delve into its inner workings to understand why your generator isn’t producing electricity.

#1 loss of residual magnetism

If your generator runs continuously but fails to produce electricity, it may be due to a loss of residual magnetism.

Generator generation involves the movement of electricity within a self-created electric field. This process is accomplished by converting a portion of the electricity generated into DC and passing it through a coil, turning it into an electromagnet.

When you stop a generator from running, it retains a certain amount of magnetic field, called residual magnetism. The generator relies on this residual magnetism to power the next start. If your generator is left inactive for an extended period, this magnetism can weaken, causing the generator to fail when you need it most.

Repair: To activate the magnetic field, you can try a method called “flashing” or “re-excitation”. This involves applying low voltage from an external power source, such as a cordless drill or 12-volt battery, to the generator.

#2 poor connections

Failure to generate electricity even when the generator is running may be due to basic reasons such as incorrect connections. If you haven’t used your generator recently or stored it in a garage or shed, dust and debris may clog the ports.

Repair: To resolve insufficient connections, thoroughly remove any particles, debris, or clogs from all ports and verify that all connections are securely tightened.

#3 tripped breaker

Just like your house, your generator has a circuit breaker that kicks in when there is too much current.

This usually occurs when the generator is overloaded to protect the system from damage. If the circuit breaker trips, the generator will not produce electricity even if it is running.

Repair: If you find a problem with the circuit breaker in your generator, you can perform the replacement procedure yourself. To replace a circuit breaker, follow these steps:

  1. Remove the spark plug to prevent accidental starting.
  2.  Unscrew the fasteners securing the receptacle housing.
  3. Disconnect the power harness and open the housing cover.
  4. Note the direction of the wires on the circuit breaker that needs to be replaced.
  5. Use a slotted screwdriver to apply pressure on the tab to release the circuit breaker.
  6.  Remove the circuit breaker cover.
  7. Insert the new circuit breaker into the slot and reconnect the wires.
  8. Follow the steps in reverse to complete the installation.

#4 broken or grounded generator excitation winding

The generator’s field winding may be damaged or grounded, which may also result in insufficient power output. This usually occurs due to wear or insulation breakdown. Over time, the field windings can become damaged, causing the magnetic field to weaken and ultimately resulting in loss of power generation.

Repair: Diagnosing or repairing a damaged magnetic field winding usually requires a professional. If you are experiencing this problem with your BISON generator, seek the assistance of a qualified BISON technician.

worn brushes

#5 worn brushes

Worn brushes and defective circuit breakers can also prevent your generator from producing electricity. If the brush is worn or damaged, it may not make adequate contact with the slip ring, affecting the operation of the generator. If a circuit breaker is defective, it may not be able to handle the load and may trip, stopping power production.

Repair: If the brushes show any signs of damage, the brushes or the entire assembly must be replaced. Fortunately, these parts are fairly inexpensive.

If you need any replacement parts, or would like to enquire about part prices, please feel free to contact us.BISON generator parts manufacturers stocks virtually all relevant parts and offers free installation guides.

#6 defective AVR (automatic voltage regulator)

Your automatic voltage regulator (AVR) ensures the stability of the mains voltage to your load, effectively protecting your generator from power sags, blackouts, and surges.

Repair: If you notice a problem with your AVR and want to replace it (BISON generator AVR), follow these instructions:

  1. Prevent accidental starting by disconnecting the spark plug.
  2. Loosen the bolts securing the generator alternator cover.
  3. Remove the two spade connector wires connected to the brush assembly.
  4. Unscrew the fasteners holding the AVR in place.
  5. Release the quick connector.
  6. Connect the new AVR to the quick connector and repeat these steps in reverse order.
defective avr

#7 faulty or broken capacitor

The generator’s capacitor serves a dual purpose: it generates voltage in the rotor and maintains voltage regulation. If there is insufficient capacitance, this results in a low voltage output, indicating that a large portion of the power comes from residual magnetism.

To evaluate the functionality of a capacitor, disconnect it from the generator and discharge the excess power.

Repair: If possible, use a multimeter to measure the reading on the capacitor. The reading should closely match the specified rating, with an acceptable range of approximately +/- 5uf, as shown on the side of the capacitor.

If the reading exceeds these thresholds, it is recommended to replace the capacitor.


After taking your generator out of storage, fueling it, and cranking it up, you may find that, although it’s running, it’s not producing any electricity or power. While this situation can be frustrating, it is a common problem experienced with generators.

A generator that doesn’t generate power is no good to anyone. In this guide, BISON outlines the common reasons why a generator’s output does not generate power when it is running. In addition, BISON provides simple solutions to this problem.

If your BISON generator is working but lacking power output and you find yourself unable to troubleshoot the problem yourself, contact one of our expert technicians who will assess and diagnose the problem on your behalf.

generator not producing power FAQ

One major factor is underuse. The magnetic reserve of the generator gradually decreases and if restarting the generator is delayed, its magnetic reserve will not be restored. Likewise, running a generator for an extended period without connecting it to a device will cause the electromagnetic field to shut down.

Likewise, plugging a device into the generator after the generator is turned off will cause the generator to lose magnetism, just as if the generator were in active operation.

The method involves "flashing" the generator field coil by applying a suitable DC voltage across the field terminals to induce a DC of the correct polarity in the field coil. This process ensures that the core retains enough residual magnetism to enable the generator to start generating electricity on its own again.

The most reliable advice includes regular use of a generator to ensure maintenance and regeneration of the device's electromagnetic field. Before turning off the generator at the end of the day, disconnect all equipment and power loads to prevent equipment from losing magnetism when powered off.

When operating a generator, it is recommended to connect it to at least one device before shutting it down, as this method has proven to be very effective in retaining residual magnetism.

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