Locking cap for oil storage tank

In combination with a storage tank including a fill opening and a hinged cap for said fill opening and whereby an outstanding peripheral flange extends about and projects outwardly from said opening, a pair of stationary mounting portions spaced along and disposed outward of one marginal portion of said flange, said cap including a pair of lug portions mounted from one marginal portion thereof and pivotally supported from said mounting portions by a pivot shaft means extending through said lug portions and said mounting portions for swinging of said cap about an axis extending between said mounting portions between a closed position overlying the outer marginal of said peripheral flange and an open position disposed outwardly of and to one side of said opening, a cap lock, said lock including a mount stationarily mounted between said mounting portions and said lug portions by said pivot shaft means and defining a recess opening outwardly thereof in a direction generally paralleling the plane of said opening, a locking body including a first portion removably lengthwise telescopingly receivable in said recess and a second portion positioned in closely spaced overlying relation with the outer surface of said cap when said first portion is telescoped into said recess preventing swinging of said cap from said closed position to said out position, and lock means releasably locking said body in position with said first portion telescoped into said recess.