Part way through the mowing season you will probably experience a lull in power and performance with your lawn mower. This usually means that your mower deck is in need of care. When the mower deck gets clogged, airflow is restricted and forces the mower to work harder. A proper cleaning of the underside of your mower should be part of the routine maintenance to ensure a long life.
Move mower to level ground near your hose outlet. Working on a concrete surface works best because you won't be working in mud after spraying off.
Unplug the spark plug according to your particular mower's instructions. Make sure gas and oil receptacles are tightly shut.
Lean mower to the side, exposing the underside.
Remove as much of the gunk as possible from the carriage and around the blade mechanism with your hands. Use a plastic scraper such as one intended for ice removal if needed. Pay special attention to the duct leading to the bagger or shoot.
Spray off with a high-powered attachment to release more of the clippings and other build-up. Repeat steps as needed.