Evaporative Check Valve: Description and Operation

OPERATION
A roll-over valve is installed between the expansion tank and the evaporative control canister. It operates through mechanical motion. The valve is a safety device that stops liquid fuel from leaking into the evaporative control canister when the vehicle is at an angle. At a specific angle, for example, roll-over of vehicle, accident, parked on steep hill etc, the valve closes and the liquid fuel can not exit the tank system.