Is there a gas cap that will allow air to go in but does not let gas fumes to escape. Or is there a valve available that can be installed that would do the same thing?
Whats the objective? Pressurize the tank? Fit a cap like this if you dont mind the judges hemming and hawwing about it. Remember to open the vent or your only gonna make it a block before you start scratching yer head... troop
Dennis, Langs cap will only reduce any liquid gasoline from escaping, but I do not think that was your question.
The gas tank vent allows the tank to remain at atmospheric pressure. Gasoline expands as it warms up and if not vented will create pressure in the tank causing flooding in the carburetor.
VW solved this problem (sort of) by attaching a hose to the cap (filler neck actually) and routing the hose outside of the car.
Modern cars use a sealed cap and vapor recovery system which reroutes the fumes back into the engine.
Since the model T carburetor is vented as well as the tank, thus achieving a balanced pressure between the two, it will be difficult to eliminate the smell of gasoline in a simple manner.
That's not really practical, and the item in the Lang's link will not do what you're suggesting. As John suggests, the pressure build-up in the gas tank, when the outside temperature rises, will cause your carburetor to leak.
If everything else is sealed well, your carb doesn't drip, your tank doesn't leak or weep fuel, and all your fuel connections are dry, the fumes emitting from the gas cap vent should be unnoticeable.
just stick a piece of chewing gum over the hole when your not using it
"just stick a piece of chewing gum over the hole when your not using it"
Not using the car.... or the gum?
haha the car!
Very true! The cap Langs sell will reduce or prevent the gas splash out of the cap vent. Air in and out, liquid will run back in and not out of the cap.