
Diesel generators are a long-term investment for businesses and residential properties. With proper maintenance, they’ll last for years, providing seamless prime and backup power. However, many people forget the importance of oil checks and changes.
Engine oil is integral to preserving your generator’s components and ensuring adequate lubrication. Failing to check the generator’s oil and change it as and when needed can cause significant damage, leading to expensive repairs or replacements.
In this guide, we’ll explore how to change generator oil quickly and safely. Let’s dive in.
Diesel generators have numerous components, each playing an integral role—including oil. Whether you have a large industrial model or a portable generator, you’ll need to check and change the oil frequently to ensure the generator remains operational.
All diesel generators are different; the frequency you need to change oil depends on your model and manufacturer’s recommendations. Here’s what you should look for when deciding whether to change the oil.
If you use portable generators for off-grid operations, you’ll need to check the engine oil regularly and change it every 50 to 100 hours of use. Standby commercial generators provide power during an outage, so they don’t require as many oil changes.
The amount you use the generator also impacts how often you change the oil. If it’s a business or residential generator mainly for standby purposes, you can wait longer, but diesel generators that regularly provide prime power can accumulate more debris, making oil changes essential.
Temperature fluctuations can impact the viscosity of engine oil, causing it to degrade quickly. Industrial and construction environments that accumulate dust and debris often need to change generator oil regularly.

Changing the oil in your generator can seem daunting at first, but once you know what you’re doing, it’s relatively easy. Let’s look at the step-by-step instructions.
Before changing the oil, it’s essential to check the levels. You can do this by using a dipstick to identify whether the oil is running low. If the generator has a lot of oil, remove it before topping the levels up, as exceeding the maximum mark can damage the engine.
Changing oil in a generator engine can be messy, so wear protective gloves and goggles. An oil funnel is also ideal for preventing spillages and ensuring the oil goes to the right location.
If your engine oil has been sitting for long periods of time, it will be sticky and cold due to debris accumulation. Before changing the old oil, warm the engine to ensure the dirt drains properly. Most manufacturers recommend running the generator at a 50% load for 10 minutes, then turning it off.
Many people find changing engine oil arduous, as it involves bending and can cause back pain. If you have equipment available, placing the generator on four identical blocks can elevate the surface and make it easier to change the oil.
However, if you have an inverter generator or a large industrial model, this won’t be possible. Asking other people to help with the change can prevent muscle strains.
Now, it’s time to remove the oil drain plug and release the engine oil. Remember, it can get messy as the oil drains, so grab something to catch it in and remove any debris from the hexagonal lid. It’s a good idea to change the oil filter, which ensures the generator will run smoothly.
Once you loosen it, just insert a new filter and make sure it’s tightly in place. Then, replace the drain plug.
Check your manual to see which oil the manufacturer recommends. Use an oil funnel to ensure minimal spillage. Make sure the oil levels are between the minimum and maximum marks.
Turn your generator on and let it run for a few minutes to check that it’s running smoothly. Assess your levels and add more oil if necessary.
Oil changes are essential for diesel generator safety, and executing them regularly can promote longevity. Once you know what you’re doing, it’s easy to fit changes into your generator maintenance schedule.
If you require any support, Solent Power is an authorised distributor of generators. We offer a range of services that help you simplify your power needs and look forward to higher productivity.

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