Abstract: An internal combustion engine includes an engine block including a cylinder, a piston positioned within the cylinder, a crankshaft configured to be driven by the piston, a fuel system for supplying an air-fuel mixture to the cylinder, and an electric starting system including a starter motor, a battery receiver, and a lithium-ion battery removably attached to the battery receiver, wherein the lithium-ion battery is configured to power the starter motor to start the engine.

Abstract: A pressure washer includes an engine, a water pump driven by the engine, a starter motor coupled to the engine to start the engine, an energy storage device electrically coupled to the starter motor, a spray device including an activation device for starting and stopping a flow of water from the spray device, a pressure sensor, and a flow sensor. The water pump has a low pressure side and a high pressure side. The high pressure side provides pressurized water. The pressure sensor is located at the low pressure side and is configured to indicate a water pressure relative to a threshold pressure. The flow sensor is located at the low pressure side and is configured to indicate a water flow relative to a threshold flow. With the engine off, the starter motor starts the engine when the pressure sensor indicates the water pressure is above the threshold pressure and the flow sensor indicates the water flow is above the threshold flow.