How to Change Lawn Mower Oil & Oil Filters

Gloved hands changing lawnmower oil filter

The right lawn mower can make cutting your grass much easier and more enjoyable. However, even exceptionally well built and designed mowers need the proper maintenance to perform. Regular maintenance is crucial to your lawn mower, improving its performance and longevity while minimizing the chance of mechanical issues.

To properly maintain gasoline lawn mowers, it’s important to perform all of the recommended oil changes. Changing lawn mower oil is imperative, as it gets dirty and degraded over time. The heat, dirt, and agitated air of your engine’s crankcase will gradually turn the oil dark and muddy, losing its ability to lubricate crucial engine parts.

Figuring out how to change oil in a lawn mower may seem tricky if you’re not mechanically inclined, however, with the right supplies and instructions, it’s relatively easy.

Change Your Engine Oil

No matter what kind of lawn mower you have, all oil changes have the same basic steps: run the engine for a few minutes to heat up the oil, drain it into a container, and replace it with fresh oil. While this is relatively straightforward for walk behind mowers, as you can simply tilt the mower to drain the oil, it’s a bit more complicated for bigger, heavier riding mowers.

If you have a Toro TimeCutter Zero-Turn riding mower, there are certain strategies that can help to simplify the process of lawn mower oil changes. Toro recommends changing out the oil of zero turn riding mowers after every 100 hours of operation, and once after the first five hours of operation for new mowers. Although this procedure varies slightly depending on your specific Toro model (check your owner’s manual for details, including important safety information), here are the basics for zero turn riding mowers:

  1.  Run your engine for five minutes or more. This warms up the oil while stirring up any debris from the bottom of the engine, allowing both to easily drain out.
  2. Park your machine on slightly unlevel terrain, so that the side with the drain is tilted downwards, sloping toward the ground. This will ensure that the oil drains completely.
  3. Shut off the engine and verify that the blade control switch is off.
  4. Prepare an oil pan, and consider putting down some cardboard to catch any spills.
  5. Locate the drain plug on the side of the engine. If necessary, attach a short length of the hose for drainage.
  6. Make sure your oil pan and cardboard are properly positioned, open the plug, and drain the oil.

Change Your Engine Oil Filter

This is also a great time to change the oil filter on your zero turn riding lawn mower. The filter traps and holds a number of impurities, so it’s a good idea to replace it with a fresh one whenever you change your oil.

  1. Locate your filter (refer to your owner’s manual if necessary) and replace it either by hand or with a filter wrench. Used filters for lawn mowers can hold a fair amount of oil, so use your drain pan and try not to spill.
  2. Once the old filter has been removed, use a clean cloth to wipe off any excess oil from the engine opening.
  3. Apply a thin layer of fresh, clean oil to the gasket of the new filter and carefully start screwing it into place.
  4. Turn the filter clockwise until the gasket contacts the engine.
  5. Tighten the filter an additional three-quarters of a turn to secure it into place without over-tightening.
  6. Wipe off the area around the dipstick, getting rid of any dirt that might fall in the filler hole.
  7. Take out the dipstick and add oil. The viscosity of your oil should depend on your area’s outdoor temperature range (check your manual or the My Toro App for details). Toro recommends using Toro engine oil for all its mowers. This oil has been tested and approved by Toro’s engineers, and meets or exceeds the engine manufacturer specifications.
  8. Slowly pour about 80% of the oil into the filler tube. Then, check the oil level with the dipstick. Carefully add more oil as necessary until it reaches the “full” mark.

Lawn Mower Oil Changes: An Overview

While you should always default to the directions outlined in your owner’s manual, the basics of how to change oil in lawn mowers are fairly simple — whether you have a walk behind or riding model. Just heat up your oil, drain it into a container, and replace it with fresh oil. Add in an oil filter change, and you’re well on your way to hours of trouble-free mowing. For more maintenance advice, read about engine maintenance tips for zero turn mowers.

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