Quick release drain plug

A drain valve assembly for attachment to the threaded drain opening of an automobile crankcase comprising, in combination:

• an anchor plate for engaging the crankcase, said anchor plate having an opening for receiving the shaft of a crankcase drain plug;
• a crankcase drain plug having a threaded shaft extending through the anchor plate opening for engaging the threaded crankcase drain opening and compressing said anchor plate against the crankcase as said drain plug is tightened in the threaded crankcase drain opening, a tightening head formed on one end of said threaded shaft, a bore extending axially through said shaft and tightening head defining a drain passage, and a counterbore formed in said tightening head defining a valve seat;
• a valve release plate pivotally coupled to said anchor plate for movement from a first position in which said valve release plate is overlying said drain passage to a second position in which said valve release plate is standing clear of said drain passage;
• a valve closure member mounted onto said valve release plate, said valve closure member being moved into and out of sealing engagement with said valve seat in response to movement of said valve release plate to and from said first and second positions, respectively;
• mutually engagable fastening means secured to said anchor plate and to said valve release plate for maintaining said valve closure member in sealing engagement with said valve seat when said release plate is in the first position, said fastening means being manually releasable to permit movement of said release plate to the second position for drainage of the crankcase;
• and,
• said anchor plate having an offset panel portion defining a latch compartment, said panel portion having an access opening, said mutually engagable fastening means including a spring wire received within said latch compartment and secured at opposite ends to said anchor plate, said spring wire overlying said access opening and a stud fastener rotatably mounted on said releast plate and insertable into said access opening when said release plate is in the valve closed position, said stud fastener having a spiral cam for locking engagement with said spring wire.