my 63's gas tank contracts and expands and makes noises doing so, i have a single outlet sender ( so no vent or return ) and a new vented cap, anything i can do to quiet this monster???? last owner drilled out cap, don't want to go that route.

 

If you have the 1963 Olds Chassis Service Manual look under fuel and exhaust section and see how the tank vents. It shouldn't do that.

 

i did, tank has vent hose that goes to filler neck, so all venting is through cap. had tank out, both vent ports are clear.