Liquid Check Valve

Fig. 16 Liquid check valve. Tank mounted type:

Fig. 17 Liquid check valve. Externally mounted type:

This valve, Figs. 16 and 17, contains a float and Viton needle assembly. Should liquid fuel enter the check valve, the float will rise and force the needle upward closing the vent passage and preventing fuel from flowing through the valve. Two different design valves are used, one picks up vapors from the lines while the other picks up vapors from the fuel tank. Both operate the same.
After passing through the check valve, the fuel vapor is routed forward through a vent line to the vapor storage canister in the engine compartment.