Pressure Vacuum Filler Cap

The fuel filler cap incorporates a two-way relief valve that is closed to atmosphere during normal operating conditions. The relief valve is calibrated to open when a pressure of 10.9-13.5 kPa (1.6-2.0 psi) or vacuum of 1.0-2.0 kPa (.15-.29 psi) occurs in fuel tank. When pressure or vacuum is relieved, valve returns to normally closed position. The cap must be replaced by a similar unit if replacement is necessary.