Gather what you need First gather your tools and equipment. You will need a power drill eye protection work gloves and a blade sharpening kit. The kit should come with a ceramic blade sharpener and balancer. Expect to pay about $8 for the kit at your local hardware store. You will also need a torque wrench (or a socket wrench in a pinch) and a wooden block. Consider having a rubber mallet on hand too.
Before we get into the nuts and bolts of the Honda 21-inch Variable Speed 4-in-1 Gas Walk Behind Self Propelled Lawn Mower we should point out that the model numbers HRX217VKA and HRX217K5VKA are used interchangeably by Honda to refer to this lawn mower and there do not appear to be any differences between the two. That said the best adjective to describe the HRX217VKA is powerful.
Place a drip pan or other container on the side of the mower with the filler. Carefully tilt the mower so oil drains out and into the pan. Discard the spent oil into a proper disposal vessel. Now slowly pour fresh oil into the mower. For the specific type of oil you need check your instruction manual. Make sure to add only as much as your particular model requires. Remember to let the mower sit undisturbed for a few minutes so the oil settles properly inside the engine.