Turn off and cool down the entire trash or water pump to prepare it for draining. This may take a few hours, depending on the size of your pump. Unplug the pump if it is an electrical unit.Drain out all the water inside the pump by tilting the unit to take out all its contents. For larger pumps, you may need to leave it tilted for a few days to completely drain it of water.
Take out the cover of the pump and clean it with a piece of cloth to get rid of minor debris. Use warm water and soap to clean the entire surface of the pump; use a dry cloth to wipe it dry. Leave it to dry for a few hours to prevent any rust forming while you winterize the pump.
Coat the entire inside surface of the pump with light oil to prevent the buildup of rust. Apply duct tape to secure all its suction ports to prevent insects from nesting inside the trash pump during winter.
Remove the engine’s oil with a suction pump and pour new oil into the compartment with a funnel. Check the user manual if you are not sure which oil to use for its engine.
Take out the air filter and dispose it of it, then unscrew the cap of the fuel tank to remove all the remaining fuel.
Wrap the pump with an old cotton sheet, and use a piece of rope to secure the wrap. Wrap it with a layer of tarp and store it in a dry area.