FUEL TANK SYSTEM FOR A MOTOR VEHICLE

1459503 Venting petrol tanks NISSAN MOTOR CO Ltd 12 Feb 1974 [17 Feb 1973 (3)] 6355/74 Heading B8V [Also in Division F2] A motor vehicle includes a hinged cover 24 for a bodywork recess in which the petrol tank filler cap 13 is situated, the cover controlling a valve 61 in a line 19a, 19b for venting the tank 11 via vapour/liquid separator 16 and valve 18 to the engine crankcase or air cleaner. Valve 61 is open when the cover is closed and closed when the cover is open. Valve 18, which may take several forms, Figs. 3-8 (not shown), relieves tank pressure and/or suction greater than a first predetermined value. If the pressure/suction exceeds this value, due e.g. to a blockage in the normal vent line downstream of junction 19b/22, a valve 21, which opens in response to a pressure/ suction value greater than the first value, provides a vent path to the space behind cover 24.