Tee valve assembly

A valve for interconnecting a tank with a fluid line wherein the tank includes an access opening encompassed by a mounting surface, in combination, a hollow body having a fluid line port having a longitudinal axis, a tubular extension defined upon said body having an axis transverse to said port axis, a mounting surface defined on said body about said extension whereby said extension is receivable within the tank opening and said body mounting surface engages the tank mounting surface, said extension including a side wall, an opening defined in said side wall, a valve axially movably within said extension between a closed position sealing said opening with respect to the interior of said extension and an open position permitting flow through said opening, first and second pressure faces defined upon said valve both exposed to fluid pressure within said body wherein pressure upon said first face when said valve is in the closed position forces said valve toward said closed position and pressure upon said second face forces said valve toward said open position, said first face having a greater area than said second face whereby the greater pressure on said valve is in the direction toward said closed position, a manually operated valve actuator mounted upon said body operatively connected to said valve controlling movement of said valve between said open and closed positions, and locking means associated with said actuator selectively locking said actuator in a position to maintain said valve in said open position.