July 18, 2024

How To – Onan Generator Oil Change

In this article I’ll walk you through the step-by-step process of performing an oil change on your Onan RV generator. The Onan generator manual recommends changing the oil each year or every 100 hours of use. This is a maintenance task that you could certainly do yourself.

A really cool aspect of traveling in an RV is the ability to be self-sufficient. With an onboard generator you can generate your own electricity when you need it. Like any other engine though, your Onan generator requires routine maintenance and attention.

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How to keep your generator healthy

1. Run the generator at least once a month

A healthy generator is one that gets regular exercise. Whether you use your generator or not, you should start it up periodically and let it run with an electrical load on it. I run my generator for about an hour each month. While running, I’ll turn on my A/C and electric water heater. When you run your generator it circulates your oil and lubricates the components. It also gives you confidence knowing that it will fire up when you need it.

2. Change the oil at least once a year

The Onan generator manual recommends changing the oil each year or every 100 hours of use. Changing the oil is not difficult and takes less than an hour. If you’ve changed oil on a car or lawn mower, then you will a familiar process for you. Just make sure you have the right tools and materials before you start.  Click below to watch my video and see how easy it is.

Please not that there is no oil filter on my MicroQuiet 4000 generator. Other models do have oil filters that will need to be changed, so review the manual for your model before taking on this project.

Tools and materials you’ll need before you start

Step-by-step oil change procedure

  1. Run the generator for a few minutes to warm it up before you drain the oil
  2. Shut down the generator
  3. Using T-30 Torx bit/socket, remove the green panel on the underside of the generator that covers the drain plug (see photo). Note: You only need to remove one screw then loosen the other. Then just swing the panel off to the side.
  4. Using the 9/16 socket, remove the drain plug
  5. Drain the oil into your oil pan until all of the oil is drained
  6. Apply some pipe thread sealant to the drain plug and screw it back in. Use a torque wrench if you have one to ensure you don’t over tighten it. Check your manual for the recommended torque
  7. Remove the oil cover and add 1.6 quarts of new oil. Note: Check your level to make sure you don’t over fill

That’s it, you’re done! Run the generator for a few minutes and check for leaks before screwing the drain plug panel back on.

Other things to check

Before I button up the generator, I take a few minutes to inspect the air filter, and wipe down visible areas. Finally, I log the date and generator hours in my RV maintenance log.

Where to get more information

Many of you have questions that I don’t necessarily have answers to, so I’ve added some links here that may help:

Related Information

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