Does My Mower Need Oil? – beginners guide with pictures

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 level indicating marks, 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”.

Dipstick marks

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 it’s 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 an 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 seats 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 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

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 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, that 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

Removing Oil

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, 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 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