How Do You Troubleshoot a Generac Generator?

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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There is no time you will need to use your generator without an emergency of some sort. Therefore, the generator has to start at all costs. If you have trouble starting the generator, troubleshooting is the way to go. So, how do you troubleshoot a Generac generator? Here are some ways you want to try out before you rule out the generator as dead or call for professional services.

a) Overheating

You need to ensure the generator is not overheating. Luckily, Generac will have the high-temperature light on to show you that the temperatures are higher than normal. Unfortunately, the standby generator is not exempt from one of the most common problems: overheating. If overheating is the case, unscrew the oil cap and on the crank case and add some motor oil to the engine cranks. Ensure the generator is off when you do this.

Overheating can be caused by a low coolant level. Ensure there is no leaking before you fill the generator with a coolant. Leaking can occur when the generator is corroded. Corrosion can be a result of many things.

b) Spark Plug

You need to ensure the spark plugs are in good condition. If the spark plug is dirty, the Generac home generator will have some trouble running. Spark plugs may be bad even when they look okay to the eye. If the generator does not start operating, you may need to replace the spark plug.

When cleaning the spark plug, do not forget to clean the cylinder. We would strongly recommend always having an extra spark plug at hand.

c) Air Filters

If you want to fix the generator that is not starting, the air filter is one feature to look at when troubleshooting. For the generator to function, it needs some air to flow. The air flow is vital so that the generator will not function without it. Replace any filters that look tough and worn out as soon as possible to protect your generator.

d) Dead Battery

Some Generac generators use batteries to start, just like a car would. If the battery is dead, there could be a chance that the generator will not start. If you have ascertained that the battery is the problem, change or replace battery to bring the generator back to life.

e) Confirm Fuel Pressure

Before you attribute any problems to a generator internal failure, you need to confirm the fuel pressure in the generator. Generac generators produce maximum power and require the correct fuel pressure to run. If you get the fuel pressure incorrect, the generator might not start. Replenish fuel tanks where there is more needed. The fuel tank should be full to avoid fuel being the issue. A defective oil pressure switch can sometimes be a cause for worry.

If you are using natural gas, ensure there is enough.

f) Tripped Circuit Breaker to the Regulator

Electrical power failure is often caused by the circuit breaker tripping when the engine starts hard or when the generator is running. Generac produces generators that provide maximum power. Therefore, the voltages can get high sometimes, depending on the house wiring. You can replace the main line circuit breaker, especially if your load in the house has increased.

More Things to Troubleshoot

There are several reasons why the generator will not start. Some of the reasons are the ones we have listed above. However, there are more things to watch out for.

  1. An uneven surface can cause problems. Ensure the generator is on a level surface and the spirit level is at the center. Otherwise, the generator would stop functioning.
  2. Check for any leaks. They are never good news.
  3. Check for a defective starter motor on the unit.
  4. Ensure the fuel valve is clean and configured at all times.
  5. Defective starter contactor
  6. Check if the fuel line is unclogged. Fuel lines have a tendency of blocking.
  7. Ensure there are enough gasoline, gas or oil levels before you start any maintenance and repair work on the unit.
  8. Replace or check air cleaner.

Final Take

Replacing your generator is not the first option when there is a problem. First, you have to troubleshoot to see if it is something you can repair yourself. Different brands have different setups, but Generac generators are made to make it easier to troubleshoot. Most people freak out needlessly if the generator runs rough or is shut down. Use the tips above to sort out any issues that may arise.

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Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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