Lawnmower engine oil is vital to lawnmower performance. Filling the engine with the right oil is essential for smooth operation. The choice of lawnmower oil is determined by the lawnmower size, the climate of the area you live in, and whether the mower is for commercial use or residential use.
Different types of oils are recommended for varied temperature ranges. SA30 is suitable for small engines in warm temperatures, while SAE10W-30, SAE 10W-30, and SAE 5W-30 are multigrade oils perfect for varying temperatures. Synthetic and synthetic blend oils are better performing graded oils options.
How do I know my lawnmower needs oil?
The right amount of oil in the engine is essential to the functioning of the mower. Low oil levels in the mower damage the engine from excessive heat and friction. The wear and tear might lead to a complete engine seizure.
Some mowers have a switch that makes it impossible for the mower to move if it needs oil. However, you will need to manually check oil levels for most mowers. Checking oil levels also lets you know when the mower needs an oil change.
Use a dipstick or dipper to check the oil levels. If the level is above the lowest mark and the color of the oil isn’t dark, there’s no need to change the oil. Drain all the old oil if the mower is due for an oil change. Then replace it with new oil.
How to check the oil in your lawnmower
- Keep the mower flat on the ground and allow the oil to settle. Let the mower rest for 5-10 minutes after using it before checking oil levels.
- Use the dipstick on the side of the engine. The dipstick is sometimes marked or colored. The dipstick has a lower mark and an upper ark. The goal is to have the oil at a point between these two marks.
- You need to refill if the oil is below the minimum mark. If the oil is above the maximum mark, remove the excess to avoid damaging the engine.
What kind of oil does a lawnmower take?
The Society for Automotive Engineers (SAE) grades lawn mower engine oils by their viscosity. Viscosity, the thickness or thinness of the oil, determines how the oil flows at different temperatures.
Most walk-behind lawnmowers use SAE30. It is a single-weight oil designed for older, smaller engines.
SAE30 is a single-grade oil whose viscosity changes with the temperature. You will have to change the oil depending on the outside temperature.
According to Briggs and Straton SAE30 oil is designed for temperatures between 40-1000 Fahrenheit. An example of SAE30 engine oil is Pennzoil Motor oil.
- It is the engine oil most suitable for small engines, like the lawnmower engine.
- SAE30 is a common oil which makes it an affordable oil for most households.
- It cannot hold up in extremely low temperatures
- It is not suitable for newer lawn mowers that are designed for multi-grade oils.
SAE 10W-30 is a type of oil designed for cold and warm climates. It is a multigrade engine oil with additives to change its viscosity. This oil is preferable for colder weather because it is thinner, giving it easier flow vital for winter.
The 10W part refers to the grade of winter oil in the mixture, while the 30 is the protection offered in hotter climates.
10W-30 is designed to protect engines that have a high-temperature range. 10W-30 oil is used on newer, more efficient, and sturdier engines.
- It is flexible in extremely cold temperatures.
- It has a lower temperature range than SAE5W-30 in a cold climate.
This oil has a lower viscosity than 10W-30. It is designed for colder conditions and icy climates. This oil is thinner and lighter than SAE 10W-30.
According to Briggs and Stratton, you should use SAE 5W-30 for temperatures below 400 Fahrenheit.
- Better than SAE10W-30 in cold temperatures
- Not suitable in high temperatures since it is thinner
Synthetic and part synthetic oils
The oils above are categorized in grades. They are also available in synthetic forms or regular oils. Fully synthetic oils are suitable for high-performance lawn mowers such as commercial lawnmowers. This is because they lubricate better even at the widest temperature range.
Synthetic oils provide premium engine lubrication and have high engine performance. Synthetic oils are highly efficient in extremely cold or hot climates. However, they are costlier than other oil types.
Part synthetic oils are a blend of synthetic and regular oils. They are an affordable alternative to synthetic oils offering the same high performance as synthetic oils.
- Synthetic oils have a higher temperature range than conventional oils
- They lubricate better and collect dirt and debris from the system because its more slippery
- Synthetic oils are more expensive than regular oils
- They burn off faster because of their efficiency, increasing the cost.
Note: Check your lawn mower’s engine manual to know the most suitable oil for it.
Can you use car oil in lawnmowers?
Typically, car oils are not designed to withstand the high temperatures that small engines can experience. Still, you can use car oil in lawnmowers ONLY IF you use high-quality oil in your car.
Lawnmowers have either a two-stroke or four-stroke engine. The four-stroke engine can use regular car oil, while a two-stroke engine cannot use regular car oil exclusively.
Motor oil can cause severe damage to the two-stroke lawnmower engine. Car oils also have detergents and additives that wear down small engines.
Multigrade oils such as 5W, 10W-30, or 10W-40 are the only ones with the quality suitable for car engines and lawnmower engines. These oils can work in different temperatures. The car oil that you decide to use should have fewer additives and enough zinc.
These are the problems you might get if you use the wrong engine oil for your lawnmower.
- The friction makes your engine slow and glitchy.
- The engine burns the oil and releases white smoke.
- The engine will overheat and get damaged.
Take caution to protect the lawnmower engine parts when using car engine oil. Follow the manufacturer’s instructions to know the right oil for your mower.
Do lawn mowers need oil in the gas?
Technically, lawnmowers need oil in the gas. However, you can only mix oil and gas in 2-stroke lawnmower engines. They have smaller engines with multiple moving parts. Hence, they are designed to use gas and burn oil in the same chamber.
You will damage your 4-stroke engine lawn mower if you mix gas and oil. Since they are bigger, they have different chambers for oil and gas.
Each 2-stroke mower has a different engine to gas ratio. For example, Briggs and Stratton 2-stroke mowers need a 50 parts gas to one part oil ratio to function.
Check the manufacturer manual to know if your mower engine is suitable for oil and gas mixing.
Can I use 10w40 oil in my lawnmower?
You can use 10W40 oil in a four-stroke lawnmower. SAE 10W40 oil is better than 10W30 oil at protecting the engine from wear when the engine is hot.
However, 10W-40 oil may not suit your engine due to additives. Additives usually dilute the oil and cause mechanical problems.
10W40 engine oil is a multi-viscosity oil with a low-temperature viscosity of 10 and high-temperature viscosity of 40. It works in most mowing conditions, from temperatures as low as -100 F to as high as 1050 F.
Although 10w-40 oil can work in many engines, read your lawn mower manual and measure the temperatures to determine if it’s the best oil.
How much oil does a lawnmower take?
The amount of oil that a lawnmower need depends on the lawnmower type and its engine size. The oil capacity is usually mentioned in the manual for most engines.
You can use these estimates to guide you for the different types of lawnmowers.
Walk-behind lawn mower
Most walk-behind types require about 15oz-18oz. Some types need about 20-24oz. You should change the oil after 50 hours or annually, whichever comes first.
The typical amount for a riding lawn mower is 48-64 oz. Also, change the oil every 100 hours or annually, whichever comes first.
Too much oil in the lawnmower can cause white smoke and oil leaks. In some cases, the engine won’t start.