Rollover Valve: Description and Operation

Check And Cut Valve:

PURPOSE
^ To prevent tank damage, vents atmosphere if tank pressure exceeds approx. 0.78 - 1.0 psi (5.37 - 6.87 kPa).
^ To prevent tank damage, allows air from atmosphere to enter if tank pressure is approx. 0.14 - 0.71 psi (0.98 - 4.91 kPa) less than atmospheric pressure.
^ Blocks fuel from leaking through evaporative system in event of vehicle rollover.

LOCATION
On fuel tank.

OPERATION
A two-way valve that vents either direction depending on pressure. Valve also contains a gravity sensitive shut-off to prevent liquid fuel from passing when it is upside down.