Every 4-cycle engine requires engine oil, unlike 2-cycle engines in which oil is added to the fuel for lubrication. Four-cycle engine oil is stored in a reservoir and distributed among the working parts of the engine when the engine is started. Over time some of the oil is burnt off in the cylinder along with the fuel. You should check the oil level often in your Honda lawnmower, definitely before each use.
Wipe any oil residue or grass clipping debris away from the oil cap with a cloth rag. Unscrew the oil cap on the right side of the engine.
Pull the oil cap/oil dipstick out of the oil reservoir, and wipe the oil off the dipstick with a cloth rag.
Place the dipstick back into the oil reservoir, and screw the oil cap back into place.
Remove the oil cap/dip stick again. The oil level will read on the dipstick. A series of X-shaped hash marks are towards the end of the dipstick. No hash marks are on the very end of the dipstick. The hash marks indicate the recommended upper oil level and the recommended lower oil level. The oil level should fall within the hash marks.
Add 10W30 engine oil to the oil reservoir if the oil level is low on your Honda lawnmower. Wipe any oil spillage away from the oil reservoir opening.
If the oil level does not read on the dipstick, the engine may be burning excessive oil and may require servicing by a qualified service dealer.