The easiest way to change the oil will be to turn the mower on its side with a container under the dipstick tube to catch the oil. It will drain better if you run the mower for about 5-10 minutes before you change it (warm oil drains better than cold). Allow the oil to drip for a little while as it's good to get all of the old oil out.
When it's down draining, tip the mower back upright and fill the crankcase with oil. The manual calls for 30w-HD (30 weight, high detergent) oil. The engine will take between 1/2 and 1 quart. I usually will start with 1/2 quart then add a few ounces at a time and check it with the dipstick until it's full.
So you are aware, I went
and found the owner's, engine, and parts manuals on their website. I went ahead and got you the requested information though.
If you have any further questions I have no problems pulling those manuals up and helping you out. We're happy to help.
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