These valves are for use on fuel tanks to comply with the CARB and EPA standards and meet the requirements of USCG Safety Standards.

The Fuel Fill Limit Valve is used to establish ullage (air space) in the tank to help prevent overfilling. The FLV incorporates a small float mechanism which, as the tank is filled, rises to seal off air escaping through the vent line. When the float rises and air can no longer escape, pressure builds in the tank and fill hose, and is sensed by the pressure shut-off mechanism in the dockside fuel pump.

To prevent fuel vapors escaping into the atmosphere, the vented air from the tank is ported via a 5/8″ hose back to the receiving 5/8″ hose barb on a vented fuel fill fitting.

Note:   FLVs do not connect to carbon canisters — those deal with vapors generated by thermal expansion, not refueling.

Perko Part Numbers:

• 0586T00038 – 3/8″ Ullage
• 0586T00034 – 3/4″ Ullage
• 0586T00118 – 1-1/8″ Ullage
• 0586T00112 -1-1/2″ Ullage