The oil reduces friction between moving metal parts and protects the life of your engine.
Read on to learn how to properly check, add, and change the oil in your lawn mower.
When Should I Change My Lawn Mower Oil?
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Change the oil in a lawn mower engine at least once a year.
If you use the mower heavily or it is older, you may need to change it more often.
New lawn mowers should get an oil change fairly early.
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Some manufacturers recommend an oil change after the first five hours of use.
Different Types of Lawn Mowers
Four-stroke lawn mower engines come in several variations.
More complex lawn mowers orriding mowersmay closely resemble motorcycle engines and have an oil-level dipstick and oil filter.
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Getting the level wrong may have consequences.
Underfilling an engine causes it to overheat, damaging the piston and cylinder walls.
Overfilling the engine makes the excess oil seep into various mower parts, causing them to malfunction.
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Confirm this with a second reading.
When you inspect the dipstick, check the oil level and how clean or dirty the oil looks.
Do not overfill the crankcase since over-filling can cause problems.
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You are more likely to make a mistake if you rush.
Screw in the Fill Plug
Screw the fill plug back into the crankcase.
You are now ready to mow your lawn.
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Tip
Check your mower engine before every use.
Have an oil pan ready to catch the oil as you drain it out of the crankcase.
Start up the mower and let it warm up for about one minute.
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This slightly warms up the oil and makes it drain out easily.
Shut off the mower, then disconnect the spark plug wire from the spark plug.
Use rags to wipe away the area around the fill plug and drain plug areas.
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This will prevent gasoline from draining out of the machine.
Place the oil pan under the mower.
Use a socket wrench in a clockwise direction to unscrew the oil drain plug.
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Allow the oil to drain out into an oil pan.
Replace the drain plug into the drain opening, making sure it is tight.
Transfer the old oil into a container you might seal for proper disposal.
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Never pour used motor oil onto the ground or down a drain.
But the filter should be changed at least once each year, or whenever the manufacturer recommends it.
Locate the oil filter, and remove it by twisting the cartridge counter-clockwise until it screws loose.
Often you might do this by hand, but a filter wrench can make this easier.
Carefully wipe off the metal rim where the oil filter seals against the engine.
Examine the rubber seal on the new oil filter.
Tighten the filter a little bit more using a filter wrench.
Refill the Engine Oil
Remove the oil fill plug on the mower.
(Some mowers may have two plugs; either one can be used to fill the crankcase.)
Use only the amount of oil recommended by the manufacturer and avoid overfilling.
As the level nears the full amount, use the filler plug dipstick to check the oil level.
see to it to wipe the filler stick clean before each check.
Reconnect the spark plug wire.
Get Ready to Mow
Your lawn mower oil is now changed.
confirm to check the oil level and the condition of the oil before every use.
Check the oil with the dipstick.
A mower typically uses fresh SAE 30 motor oil, but always check the lawn mower manufacturer’s recommendation.
