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Can the Mocal tank valve M-TRV67 which has a -6JIC thread be used to vent a fuel tank when filling it with fuel? Does the valve prevent large amounts of air to escape?

When this Mocal Tank Breather valve is installed it will allow air to breath in both directions to stop the build up of pressure or vacuum in the tank, then if the car is up side down, following an accident, a ball bearing drops over the hole preventing the fuel from escaping. So when you are filling the tank air will be forced out of this valve as there is no flap or anything to stop the flow of air, it is completely open. The is a second lightweight ball that floats and seals the valve if the fuel in the tank surges in a corner. If you want a valve that has a diaphragm in side that requires a couple of PSI or either pressure of vacuum before it lets air past then you will need the Mocal valve TPV8 This is not a roll over valve that you would use on a competition car.

Archived in: Roll over fuel tank valves

11th June 2015

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