How to Check the Oil on Your Generac Generator – Important: Check oil every 12 hours of continuous use!

Watch Snow Accumulation

Make sure your generator is shoveled out when more than 12 inches of snow has accumulated. Most residential generators are air-cooled and must be able to intake and exhaust air from either side of the generator to operate properly.

Check your oil every 12 hours

Generators that are running for long periods of time need to have the oil checked every 12 hours of run time.

  1. Open the generator housing.
  2. Turn off the breaker (looks like a house breaker), which is located on the side of the generator. This will cause the lights/loads to shut off but the generator will continue to run.
  3. Locate the controller inside the generator (see illustration 1) and move the rocker to “RESET” or “OFF”. This will cause the generator to shut off.
  4. Locate the dipstick and check the oil level.
  5. If oil is needed, unscrew the oil fill cover.
  6. Add oil in slow increments (you don’t want to overfill) and fill to “FULL” mark on the dipstick as needed. Oil type: 5W30 Synthetic.
  7. Replace dipstick and the oil cover.
  8. On the controller, reset the rocker to “AUTO” – this will cause the generator to start.
  9. Wait 10 seconds and turn on the breaker – this will cause the lights/loads to come back on.
  10. Close the generator housing.

Tips & Responsibilities

  • Keep an ear open for the weekly exercise of your generator. If you have not heard the generator run for a couple weeks, let us know and we will help you determine if there’s a problem.
  • Keep your generator in a clear area.  The generator needs air to work properly. Take some time to clear the snow away from the generator after a winter storm, and clear away any summer overgrowth from around the intake and exhaust areas of the generator.
  • Keep the generator easily accessible. If the generator is in a confined space, our service techs might not be able to service or fix your generator.