C1 gas tank venting

[Michael Jones]

Could someone tell me why Chevrolet put a vent line in to the C1 gasoline tank along about the '58 model or so? I'm trying to sort out a gas feed problem.

Thx,

Michael

[Tom Spurgeon]

Re: C1 gas tank venting

Michael,
My "assumption" would be that when the gas cap is applied, to allow for the flow of gas there would need to be equal pressure from the suction created by the fuel pump.

[John H.]

Re: C1 gas tank venting

The original arrangement had no tank vent, and used a vent valve in the filler cap instead; this became infamous for fuel spillage through the valve in the cap, especially in right turns with more than a half-tank of fuel. In mid-'57 the tank vent was added with the vent line and hose into the filler cap cavity and added a non-vented sealed fill cap, and many earlier cars were converted in the field under a Service Letter.