How to Change Oil In RV Generator (Cummins Onan)

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In this article, we will check in detail the steps in Onan Generator Oil change.

One of the fascinating things about traveling in an RV is that they are self-sufficient. An RV gives you the freedom to travel anywhere, anytime you want.

With built in Cummins Onan RV generator, you will be able to generate electricity anytime you need it. For the generators to last long and give you a hassle-free operation, they will need proper care and regular maintenance.

One of the ways that will help increase the longevity and performance of your diesel RV generator is changing the oil regularly.

RV generator service is based on the hours they run. For Onan and Cummins diesel generator, it is recommended that you change the oil after every 100 hours of use.

Changing the oil for your RV generator is an easy task that you can do yourself.

The whole process of changing oil takes about an hour. To get started, make sure you have the right tools and materials.

You will need an oil pan, a funnel, a T-30 Torx bit, a socket, and oil for the generator.

Lets check out Onan generator oil change procedure.

Changing oil in RV generator

Here is a step-by-step guide for changing the oil in an RV generator – Onan or Cummins.

1. Run the Generator For Few Minutes

The first step to changing the oil in your RV generator is to run the generator for a few minutes.

This helps to warm up before you can start draining the oil. It is recommended that you let the generator run for about five minutes and then stop.

This step is necessary to ensure that all the oil in the generator is drained without leaving any residue.

You should be cautious to ensure that the oil does not heat up completely since it will be difficult to drain.

2. Shut down the Generator

After running the generator for a few minutes, you can now shut it down.

This is to ensure that the generator does not get over-heated and also to avoid consuming the oil that you want to drain.

3. Remove the Protection Plate

The next step is to remove the green protection plate that is located under the generator.

This plate is used to protect the drain plug underneath the generator. The best way to remove the protection cover is by using the T-30 Torx bit.

This will help you remove the cover safely without damaging it. To have an easy time in this step, you only need to remove one of the screws, and then you can loosen the others.

Once you have removed all the screws, you can now swing the cover off to the side.

4. Remove the Drain Plug

In this step, you will need the 9/16 socket or 12mm socket to remove the drain plug. You should be very careful in this step to ensure that you do not spill the oil over the place.

5. Drain the Oil

Finally, you can now drain the oil so that you can replace it with new oil for the generator.

In this step, you will need an oil pan for draining all the oil. Make sure you hold the oil pan in place to avoid spillages.

Then allow all the oil to drain until there is no oil left in the generator for increased performance.

After draining the oil, make sure you understand the right measures of disposing of the oil to avoid damaging the environment.

6. Install the Oil Drain Plug

Once you have completely drained all the oil, you should now install the drain plug into the right position.

However, do not install the protector cover for the drain plug at this time.

To install the drain plug, you will need to screw it back in. To make sure it’s completely sealed, apply some sealant on the drain plug and screw it.

You can use a torque wrench on the screws but make sure you do not over-tighten it. This is to make sure you do not have difficulties the next time you want to change the oil.

7. Fill the Generator with New Oil

Change oil in Cummins Onan RV QG 4000 Generator

In this step, you will need to have 1.6 quarts of Onan or Cummins approved oil.

Remove the oil cover and add the new oil into the generator. It is important to inspect the oil drain plug to ensure there is no leaking. If you find some leaks, do not add more oil until you seal the leaks.

Make sure you only add enough oil and avoid overfilling by constantly checking the oil level.

Once you have filled the generator with enough oil, start the engine and turn it off to check for any leaks. You can now install back the drain plug protector.

8. Inspect the Oil Filter

The last step is to inspect the oil filter. This is to check for any leaks and check the level of the oil.

To check the oil level, you can use a dipstick at the oil fill location. If the level of the oil is good, you are good to go, but if the oil is not enough, add more.

In this step, it is essential to check the generator’s air filters to ensure they are in good working conditions. Additionally, wipe any spilled oil from the generator and disposed of the used oil safely.

It is recommended that you read to the generator’s manual for safety purposes and make sure you do not skip any important steps.

Check this Onan RV 4000 Air Filter.

How Often to Change the Oil in RV Generator

How to change oil in Onan 5500 Generator

For Onan and Cummins RV generators, it is recommended that you change the oil after every 100 hours of use. If you do not use your RV regularly, this should translate to changing the oil once a year.

However, you should perform the task more often if you travel with your RV in dusty and hot weather.

Changing the oil will guarantee you increased performance and durability of your RV generator.

RV in built generators like Cummins Onan running on gas/diesel can run continually for as long as 30,000 hours provided good care is taken. Hours will reduce based on maintenance neglect, start/stop, oil draining, air filter quality.

Check out the Tune Up Kit for Onan 5500 and Onan 7000 RV generator below on amazon.

What Kind of Oil to Use

The type of oil to use for your RV generator depends on the model of the generator you are using. The oil should be approved for your generator.

For the Onan and Cummins generators, you will need 1.6 quarts of SAE30 or 15W-40 oil.

Having the right oil for your RV generator provides excellent protection against oxidation, wear, and protects in water-cooled engines.

G. Yoganand

A RV enthusiast who spends countless hours researching and learning various things related to RV camping. He believes in spending time doing Outdoor activities.
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