Air Control Valve

The air control valve is located in the air supply line between the pump and check valve, The control valve is vacuum controlled. During normal operation, a vacuum signal is applied to the control valve and all the air supply is directed to the check valve and air delivery system. When the vacuum signal to the port is less than 2 in Hg, the air supply from the air pump is diverted to the engine air cleaner. When there is excess back pressure in the system, there is a spring loaded relief valve which comes unseated.