Step 3: Replace the Oil Filter (if applicable)
If your lawn mower engine model does not include an oil filter, skip to step Step 10 to complete your oil change.
6. Prepare something to catch the oil.
Unscrewing your mower's oil filter will spill the oil it is holding inside of it.
Find something to catch the oil that is small enough to fit under the filter as you unscrew it.
7. Unscrew the old filter.
The old filter simply unscrews.
8. Coat the seal of the new filter with oil.
The seal of the new oil filter needs to be coated with oil before it is installed.
Using your finger, apply a small coat of motor oil to the outside lip of the new filter. This thin coat of oil will ensure that it seals tightly when you install it.
9. Install the new oil filter.
Screw the new oil filter into place until it touches the plate it seals against. Then, give the filter a firm 1/4 or 1/2 turn to tighten it down.