Push lawn mowers use an engine to spin the cutting blades. Just like a car engine, a mower engine needs oil to prevent it from overheating and blowing up. Using the correct oil is essential to the engine's performance because if the wrong kind is put in, it will cause as many problems as it would if there were no oil inside of it.
Uses SAE 30 weight motor oil. This a very common size that is versatile due to it being thick enough to lubricate, but not so thick that it will clog engine parts.
Kind of Oil
This is the same kind of SAE 30 weight oil used in cars.
Where to Buy It
Since it is a standard oil for both cars and lawn mowers, it is available at many different outlets. Automotive and department stores that sell motor oil will carry the SAE 30. So will tool and small-engine repair stores.
What it Does
Oil lubricates the piston, valve springs and other internal parts of the motor to cut down on friction. This cools it down so that it prevents overheating. If something thicker than SAE 30 was placed into the engine, it would gum up the piston, causing the motor to move slower or not at all. If a thinner oil was placed into the engine, it would not lubricate well enough and it would overheat the internal pieces, which leads to a blown piston and broken valve spring.
Where to Put the Oil
Look for a yellow cap on top of the motor. It will have an icon that looks like an old-fashioned oil can. Pour 32 oz. into the motor or until the reservoir is filled.