Abstract: During the overhaul of an internal combustion engine, a two, four, or six cylinder head or manifold is quickly mounted at a convenient working height on a portable work stand with the fire deck surface of the cylinder head entirely bearing against a sole rubber or rubber like continuous gasket to seal off most of the entries to the internal cavities in the cylinder head, through which the engine coolant flows when an engine is running. The gasket is secured to and supported on a table, which in turn is rotatably mounted and lockable on an overall frame, optionally supported on wheels. The cylinder head or manifold is clamped to the work stand in the sealed position by selectively adjusting a securement subassembly, which is quickly utilized, and which does not obscure the inspection of the unsealed surfaces of the head, during a subsequent pressurized hot water test to determine if there are any leaks in the internal coolant cavities of the head.