Engine oil is the most important item to check on your mower. Nothing kills an engine as quickly as a low oil level, but it’s important to get it right, too much oil is also bad for the motor.
A mower engine requires oil if the oil level reads below the low-level oil mark on the dipstick. A dipstick has two oil levels indicating marks, the upper mark indicates the full level, and the lower mark the low oil level. Add oil until it reaches the upper oil level mark on the dipstick.
In this post, you’ll learn how to check your mower oil level and also how to add oil including oil type and quantities. This post should have the subject covered pretty well, but if you need video help, check out “Mower oil check video”.
Checking Mower Oil Level
Checking the mower oil level should be undertaken before every use, it only takes a moment of your time and could potentially save you hundreds of dollars. Oil lubricates and cools your mower engine, when a mower runs out of oil, the engine builds so much heat it fuses the internal components together, a condition known as seizing the engine and its terminal. The process for regular walk behind mower and ride-on tractor mower is identical.
Checking the oil should be performed while the engine is off and the mower is parked on level ground.
To check mower engine oil level, follow these simple steps:
Locate – Locate the dipstick
Clean – Remove and clean it. To remove a dipstick, turn it anti-clockwise.
Read – Refit dipstick and remove to read dipstick level.
Locate Dipstick / Oil Filler
The dipstick is usually located on the side of the mower engine. The dipstick cap is generally marked with the word oil or oil can symbol and often a contrasting color. The dipstick is also the oil filler location.
Locate – Dipstick in yellow here.
Reading A Dipstick
The upper mark identifies the full level and the lower mark the low oil level. The upper and lower marks may be letters, words, holes, or stamped lines. Between the high and low marks, you may see a hatched area. This area denotes an acceptable oil level zone, however, it is always best to have the oil level reach the upper dipstick mark.
Dipstick Markings – Dipstick markings vary, but all follow the same principle – upper is full mark and lower mark is low.
Some dipsticks employ a hatched area in-between to identify an acceptable oil level zone.
It’s important to note, while there are many styles of high and low dipstick markings, there are just two main dipstick seat flavors, threaded or winged. Do not thread home a threaded type dipstick in order to dip for oil. Doing so gives an incorrect oil level reading. See pics below or check the oil check video here.
Threaded – Threaded dipstick seat
Threaded – Do not thread to check the level
Correct Oil Level – Oil level correct (Top hole). Nice work!
Oil Low – Oil level below the critical low oil level mark (lower hole). Add oil now.
Oil Too Full – Too much oil, remove excess oil.
Adding oil is simple, fill the oil through the dipstick tube. Some dipstick tubes may be small and awkwardly located, if that’s the case you’ll need a funnel (MacGyver funnel – cut the base off a plastic drinking bottle). When filling oil just remember to add a little and recheck the oil level, repeat until the oil level reaches the upper mark on the dipstick.
Adding too much all at once will cause the dipstick to read over the full mark. Overfilling is a common error and most think it can’t hurt any, but they are wrong.
Add a Little & Check
While too much oil is better than too little, too much can still cause some problems. From empty, most mower engines won’t hold more than .65 of a quart. Ideally, a mower should get a tune-up once a year, which includes an oil change. I wrote a complete post with pics and instructions on the subject and you can check it out here.
You’ll also find a video on “Mower tune-up” here.
Symptoms associated with too much oil include:
- No start
- Pull cord hard to pull
- Starts and stalls
- Runs with lots white smoke
- Oil leaking from muffler
- General oil leaks
The first task before working your mower is to remove the spark plug wire, this prevents accidental starting. Removing oil can be a little messy, especially if you’ve just added a little too much. Knowing how much to remove is hit and miss. Most modern mowers will allow oil to drain by tilting the mower on its side, engine oil flows out through the dipstick tube. You can check that out in this video, it covers a mower tune-up.
Older mowers will have a regular oil drain plug under the mower where the blade is located and that type is messy. I prefer to use an oil extractor siphon, which makes the task simple and you use it on other jobs like draining the gas tank. If you need a siphon, I recommend the Briggs & Stratton oil and gas siphon, it’s good quality at a fair price and you can check it out on the “Small engine tools page”.
Oil extractor, the preferred method.
Mower Oil Type
Mowers will run perfectly well with car engine oil. It is of course better to use the oil type specified by the engine maker 5W30 or 10W30 works great for mower engines.
- Briggs and Stratton oil type – 5W30
- Honda oil type – 10W30
- Kohler oil type – 10W30
- Tecumseh oil type – 5W30
- Kawasaki oil type – 10W30
Check out the Amazon link below for lawnmower oil delivered to your door.Amazon Lawnmower Engine Oil
- About the Author
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John Cunningham is an Automotive Technician and writer at Lawnmowerfixed.com.
He’s been a mechanic for over twenty-five years and shares his know-how and hands-on experience in our DIY repair guides.
Johns’s fluff-free How-to guides help homeowners fix lawnmowers, tractor mowers, chainsaws, leaf blowers, power washers, generators, snow blowers, and more.