Can You Use 2 Cycle Oil In A Lawn Mower?

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Can you use 2 cycle oil in a lawn mower? The answer depends on the type of lawn mower you have. Read along to learn more. 

This article discusses the conditions when using a 2-cycle oil for a lawn mower is advisable and when it is not. In addition, you will learn about the negative impacts of using the wrong oil in a mower and the best oil for lawn mowers.

Can You Use 2 Cycle Oil in a Lawn Mower?


If you have a 2-cycle lawn mower, then yes. Otherwise, find the appropriate oil for your lawn mower. 2-cycle and 4-cycle lawn mowers differ in their mode of operation and thus require different oil types.

ACS Garden, a UK-based agricultural company, explains the distinction between the two. According to the source, “A two-stroke engine makes one rotation for every explosion.  A four-stroke engine makes two rotations for every explosion. 

Two-stroke engines have the fuel and oil (for lubrication) mixed together.  Therefore, you don’t have an oil inlet on the machine, and you only need to buy one type of fuel.”

Before using 2 cycle oil in your lawn mower, determine whether it is a 2-cycle engine or not. 

How do you do that?

To determine your mower lawn engine type, check the type and number of fill ports on the engine. 2-cycle engines usually have a single fill port for the gas and oil. On the other hand, a 4-cycle engine has two fill ports, one for oil and the other for gas.

In order not to hurt your engine, aside from knowing the engine type, you need to understand the oil/gas mixing ratio too. 

Most manufacturers recommend mixing a part of oil to 40 parts of oil for 2-cycle engines. If you use more than the recommended gas to oil ratio, the engine may smoke. The engine’s efficiency will also drop. Over time, the spark plug will stop working and the mower won’t start.

If you notice the impact of too much oil in your lawn mower, open the oil cylinder and drain the excess oil in the crankcase out. 

If you can’t do this yourself, hire an expert to do the job. When removing the excess oil, slant the mower to its side. Ensure that the carburetor faces upward to prevent some of the oil from getting into the carburetor and burning chamber where they can do more damage.

What happens when you accidentally put 2-cycle oil in a 4-cycle engine?

Accidents do happen. You may unintentionally put a 2-cycle oil in a 4-cycle engine. 

The major difference between the two engine types is that while the oil serves as a lubricant in a 2-cycle engine and thus requires mixing the oil with the gas as the manufacturer recommends, 4-cycles don’t require mixing the two. 

Thus, accidentally using 2-cycle oil in a 4-stroke engine where it won’t mix with the gas may harm the engine.

How Often Should You Change Your Lawn Mower’s Oil

How Often Should You Change Your Lawn Mower’s Oil?


Aside from knowing the right oil for your lawn mower, it is equally important that you know how frequently you should change the oil. You should consider replacing your mower oil after every 20 to 50 hours of operation, depending on your mower’s specifications. 

You may need to change your mower’s oil if you work on a large lawn or use your mower in muddy or wet grass. The type of mower you use also determines when to change your mower oil. 

The lawn mower’s owner’s manual contains helpful information about the recommended oil type for your lawn mower. If the information is missing from the manual, check the manufacturer’s website for a clue.

Temperature is another factor to consider. SAE 30 is the best oil option if you live in warmer temperatures. SAE 10W-30 oil is the recommended oil for people living in areas with fluctuating temperature between 0 degree and 100 degree. People living in colder areas should go for SAE 5W30 oil.

The mower’s engine capacity is another factor you should consider. For instance, standard oils are not ideal for 2-cycle engines. They are better off with oils with SH, SF, SJ, or SF APR performance ratings. 

Other specialized lightweight oils are good for this type of engine. You may consider synthetic oils as well. These oil types work well in different temperatures

On the other hand, standard oils are great for 4-cycle engines since they store the oil and gas in different compartments.

How to Check Your Lawn Mower Oil

Checking your lawn mower’s oil level regularly is a must. The regular checking will enable you to know when the oil level is too low and a refill is necessary. 

To check the oil level:

  • Remove the lawn mower’s dipstick cap by applying some pressure and twisting it counter clockwise.
  • Remove the dipstick after removing its cap.
  • With a clean rag, wipe it clean to ensure accurate reading.
  • Reinstall the dipstick fully back by applying some pressure and twisting it clockwise.
  • Twist the dipstick while putting it back into its place.
  • Allow the oil to settle before checking its level.
  • Remove the dipstick again and check the oil level.
  • If the oil residue is between the add marks and full marks, the oil level is okay. Otherwise, if it is lower, put more oil until the oil level is between the add mark and full mark.