Auto Drain Plug for a Filtration Apparatus

A filtration apparatus comprises a housing defining an internal volume sized to receive a filter element, an inlet for receiving a fluid and an outlet for expelling the fluid. A retention mechanism is disposed in the housing having a ball plug operatively connected thereto and selectively displaceable in an axial direction relative to the housing. An engagement member is disposed within the housing and comprises a port having an opening and a ramp. A portion of the port is disposed within the outlet. The ball plug is movable between a first position, in which the ball plug rests on the ramp, does not seal the opening of the port and fluid can be expelled from the housing port, and a second position in which the ball plug is aligned with the port, the ball plug seals the opening of the port and the fluid cannot be expelled from the outlet.