What Oil to Use in a Petrol Lawn Mower?

Written by: - Gardening Expert
Reader rating
What Oil to Use in a Petrol Lawn Mower

Your petrol lawn mower needs oil in order to run, and most lawn mower manufacturers recommend changing it after every 20-50 hours of use (or annually – whichever comes first!).

But which oil should you be using in your petrol lawn mower? Here’s what you need to know: 

The Different Types of Petrol Lawn Mower Oil 

Let’s start by talking about standard engine oil – the stuff made for cars. This is usually high quality so most lawn mowers will run just fine if this is what you use. 

However, viscosity is really important with lawn mower oil, which is why standard engine oil can sometimes clog petrol lawn mowers. To avoid this, use one of the following: 

  • SAE 30 – best for older, air-cooled engines 
  • SAE 10W-30 – a popular multi-grade oil 
  • SAE 5W-30 – another multi-grade oil, but this one is better suited to low temperatures 

What About Synthetic Oil? 

Rather than being made from crude oil, synthetic oil consists of a man-made lubricant that has been mixed with specific chemical compounds. The result is a high-performance oil that’s actually far superior to natural oils

The downside is that synthetic oils tend to be more expensive. However, if you would like to give a synthetic oil a try, two to consider are: 

  • Synthetic SAE 10W-30 – good for colder temperatures 
  • Synthetic SAE 15W-50 – best for engines that undergo heavy use, such as with commercial machines 

Always Check the Instruction Manual

Whilst oils that have a grade of SAE 30 are usually a safe bet, it’s always worth double checking the recommended oil for your lawn mower model. Using the wrong type of oil can cause some serious damage.

It can help to get into a routine when it comes to lawn mower maintenance, changing the oil at the same time as servicing your petrol mower.

READ NEXT: The UK’s Best Petrol Lawnmowers

How Much Oil Will You Need for Your Petrol Lawn Mower? 

When filling a petrol lawn mower with oil, you will likely need between 400 – 600 ml, depending on the size of your mower. Fortunately, since most lawn mower oil comes in 1 litre bottles, you should have more than enough. You should never start your petrol mower without engine oil, as this can damage the machine.

Where you put the oil will depend on whether you have a two-stroke or four-stroke lawn mower. Two-stroke petrol mowers will need the oil to be measured and mixed in with the fuel, whilst four-stroke engines will have separate compartments for oil and petrol. Again, it’s very important to check the instruction manual to make sure you’re using the right amount in the correct way.

Whether you’re filling a new lawn mower with oil for the first time, or you’re looking to make an oil change to improve your mower’s performance, it’s always worth spending some time exploring your different options.

Although higher quality oils may cost a little more, each fill will generally last for a year (unless you’re using the mower very frequently). This can help justify the extra investment. 

How useful was this post?

Click on a star to rate it!

Average rating 4.9 / 5. Vote count: 19

No votes so far! Be the first to rate this post.

As you found this post useful...

Follow us on social media!

Scroll to Top