Liquid Vapor Separator: Description and Operation

Fuel Vapor Valve:

PURPOSE
The fuel vapor valve makes use of a small orifice and shutoff valve that tends to allow only fuel vapor, not liquid, to pass into the fuel and vapor return tube routed forward to the fuel vapor canister.

OPERATION
Fuel vapors in the fuel tank are vented through the fuel vapor valve in the top of the fuel tank. The vapors are transmitted through a single vapor tube to the fuel vapor canister at the front of the vehicle. A spring loaded poppet valve provides relief ahead of the orifice to the fuel vapor canister. This valve gradually opens above 5-6 kPa (20-25 in Hg) to vent fuel vapors to the fuel vapor canister.