Too Much Oil In Your Lawn Mower? (We Have a Fix)

Jessica Stone
by Jessica Stone
Lawnmowers are delicate, and making mistakes such as using too much oil can throw them off completely. Luckily, there are several solutions such as tilting the mower to the side to remove excess oil. Whether it be changing oil properly or removing excess oil, follow along as we explore what you should do when there is too much oil in a lawnmower.

Your lawn mower needs oil to provide ample lubrication, prevent overheating, and generally work efficiently. However, what happens if you put too much oil into your lawnmower?

Having too much oil in your lawnmower can lead to motor damage and possibly an oil leak, a fire hazard. To remove excess oil from your lawnmower, you will need to tilt the mower to its side with the carburetor facing upwards. You should replace the trimmer’s oil filter once finished.

Let’s examine how you can determine whether your lawnmower has too much oil, what to do if it does, some possible effects on your mower and how to avoid this from occurring again in the future.

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What Are The Signs Your Lawn Mower Has Too Much Oil?

The following are some indications that your lawnmower may have too much oil. Look out for these signs:

  • A hard start of the motor. A surplus of oil in a lawn motor can cause the hard start of the motor. This is due to the fact that certain parts of the engine come into contact with motor oil that they shouldn’t.
  • Leaking oil. A lawnmower that is leaking oil may indicate that it has been overloaded. It could potentially be released from the muffler, exhaust, or other areas of the machine.
  • Slow starting motor. In addition to a hard-starting motor, an engine with a slow start could also potentially mean too much oil.
  • Oil in the carburetor. Surplus lubricant can flow toward the carburetor if you tip the mower at an angle or you are trimming a hilly terrain.
  • The muffler is releasing white smoke. If you notice that your muffler is emitting white exhausts, this is a tell-tale sign that your lawnmower has excess oil. Usually, this sign will be paired with visible oil coming from the muffler.
  • Oil drops on the air filter. If you have an air filter installed in your trimmer and notice oil droplets, this is a possible sign of extra oil in the system.

How Can You Check Your Lawnmower For Too Much Oil?

Regardless, the most guaranteed way to know whether or not your lawnmower has too much oil is by using a dipstick. When the mower’s engine is cold, insert the dipstick into the lubricant and check the level of the liquid. The oil level should sit between the full and add marks on the dipstick.

These are all common signals that your mower has been overfilled with oil. It’s essential that any excess is removed to enable your trimmer to function correctly again and help avoid any permanent damage.

How To Remove Excess Oil From Your Lawn Mower

Once you discover that your lawnmower has been overloaded with oil, it needs to be removed as quickly as possible to prevent any possible destruction. In some cases, it may be too late to fix the issue yourself, and you should seek the assistance of a professional.

However, if you catch it early enough and with a little patience, you can successfully drain the oil on your own. Make sure to engage in this process carefully to avoid any possible spillage.


  • Using a clean rag or cloth, clean the area surrounding the crankcase. This will help avoid any undesirable dirt or other materials from entering the crankcase during the removal of the oil. Dirt that ends up in the crankcase could potentially clog the carburetor and cause your machine to stall during use.
  • Remove the lubricant. Next, unscrew the tube on the crankcase to remove the lubricant.
  • Tilt the mower. The best course of action for removing the excess oil is to tilt the mower on its side with the carburetor facing upwards. This will also prevent any oil from draining into the combustion chamber or the carburetor itself.
  • Replace the filter. Once the extra oil has been completely drained, replace the trimmer’s oil filter. This will help ensure a long lifespan for the engine.
  • Dispose of the oil. Properly dispose of the excess lubricant in a sustainable way to help protect the environment.

With some persistence and a little knowledge in regards to proper oil removal, you will have your lawn mower operating like normal in no time at all!

How Much Oil Does A Lawn Mower Require?

Rather than guessing and possibly jeopardizing your engine, or entire lawnmower, it’s essential to research the exact volume of oil that should be added.

The best way to retrieve this answer is by checking the owner’s manual or any manufacturer instructions listed online.

The exact amount of oil will depend on the particular type of mower and the size of your engine. In general, the lawnmower oil capacity rules of thumb are as follows:

Walk-Behind Mowers

  • Oil volume is generally 15 ounces or 18 ounces.
  • Change the oil annually or every 50 hours, whichever comes first.

Riding mowers

  • Oil volume is generally 48 ounces or 64 ounces.
  • Change the oil annually or every 100 hours, whichever comes first.

What Type Of Oil Do You Use For A Lawn Mower?

In addition to the proper amount, it’s essential that you know the correct type of oil that should be used in your lawnmower.

This depends on various factors, including the type of mower you own, the mower’s engine, and the outdoor temperature in your location.

  • Type of Lawn Mower: The manufacturer of your lawn mower will generally recommend a specific type of oil. Reference the owner’s manual or check online for this information.
  • Lawn Mower’s Engine: You must be aware of the type of engine your lawnmower has to determine the type of oil it needs. Two-cycle engines cannot use conventional motor oil and require particular lightweight oil with performance ratings such as SH, SF, SG, or SJ. In comparison, four-cycle engines do use traditional motor oil.
  • Outdoor Temperature: SAE 30 is the best choice for warmer temperatures. For colder areas, still with SAE 5W-30 motor oil. However, if you reside in a location that has fluctuating temperatures, use SAE 10W-30 motor oil.

How To Change Lawn Mower Oil

For optimal performance, oil should be changed in a new mower after the first five hours of use. Then, it should be changed every 50 hours of operation or once every mowing season, whichever comes first.

  • Let the mower run. Start the engine and let it run for about 60 seconds to warm off.
  • Turn it off. Shut off the engine and disconnect the spark plug wire. This ensures that the mower doesn’t accidentally turn on while you’re working.
  • Remove dipstick. Clean old oil and grime from the dip stick shaft area and remove the dipstick.
  • Drain the oil. Drain the oil into an oil safe container by unscrewing the oil plug.
  • Replace the oil filter. This should also be done at least once a year to maintain your mower.
  • Locate the oil fill plug. With the oil filter switched out, locate the oil fill plug. This is where you’ll insert the oil.
  • Add the oil. Pour the recommended amount of oil into the hole where the fill plug goes. If your mower has two fill plugs, you can use either one.
  • Replace everything. Once all of the oil is inside of the engine, replace the plug and/or dip stick. Be sure to wipe the dip stick clean before you insert it back in.

Finish off by pulling the dipstick out again to verify that the oil level is correct. The proper oil level will be indicated on the stick. Then, add more oil or drain excess accordingly.

How To Prevent Adding Too Much Oil To Your Lawnmower

To ensure that you don’t repeat putting too much oil into your lawnmower, read your owner’s manual carefully to be aware of the oil requirements of your machine. Also, every time you refill the lubricant, make good use of the dipstick to check the oil level.

If too high, drain the excess oil immediately. At all times, the oil level should sit close to the maximum mark on the dipstick but never beneath the minimum mark.

Add Small Amounts

In general, adding cold lubricant to a cold engine can often result in too much oil in a riding lawnmower. This is due to the fact that cold oil moves much slower than warm oil.

In this case, it’s very common for people to continue adding lubricant past the amount that’s required. To avoid this issue, add a small amount of oil, wait until it settles in the crankcase, then add some more.

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Wrapping It Up

In order to ensure that your lawnmower functions efficiently, you must put the correct quantity of oil into the engine. An excess of oil can cause severe and possibly even fatal damage to the machine.

The best way to avoid placing too much oil in your lawnmower in the first place is to consult the manufacturer’s manual. This manual is an excellent resource to aid you in maintaining the proper functionality of your lawnmower.

Additionally, be sure that you do not surpass the maximum fill line on the dipstick when filling your trimmer with oil. At the first sign of too much oil, drain the excess immediately.

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Jessica Stone
Jessica Stone

Jessica considers herself a home improvement and design enthusiast. She grew up surrounded by constant home improvement projects and owes most of what she knows to helping her dad renovate her childhood home. Being a Los Angeles resident, Jessica spends a lot of her time looking for her next DIY project and sharing her love for home design.

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