Abstract: An adjustable wrench head (10) is disclosed for use in conjunction with spanner nuts of various sizes, each spanner nut having a plurality of locking recesses therein. More particularly, a wrench head is provided which includes a central elongated driving spindle (20) having a plurality of opposed pairs of planar guide rails (22, 24) projecting radially outwardly therefrom. Each pair of guide rails defines a channel (26), which is adapted to receive a generally rectangular insert (28), with the insert being radially movable therein, relative to the central spindle. Each insert is provided with a tang (30) which projects axially beyond the front end of the spindle for engagement with a locking recess of the spanner nut. The radial position of the inserts are adjusted and secured such that the tangs thereof are spaced from the center of the spindle a distance corresponding to the radius of the spanner nut.

Abstract: A work stand for rotably mounting an engine thereon during the initial construction of the engine, or for repair of the engine, includes two concentric rings which are disposed in upstanding relationship and are mounted on a base. The inner ring is rotably mounted within the outer ring and includes a plurality of axially extending arms which engage the engine. The latter is mounted in a generally horizontal disposition and is rotable with the inner ring whereby access to the engine is unobstructed from either the top or bottom of the engine, as well as along the entire length of the engine. A locking mechanism is provided between the inner and outer rings of the work stand for maintaining the engine at the desired angular attitude, and the engine is mounted such that its center of gravity is disposed adjacent the upstanding planes of the concentric rings.