Apparatus and method for detecting crank shaft orientation and valve assembly in an internal combustion engine

Apparatus for the automatic inspection of a multicylinder four-cycle internal combustion engine having a crankshaft;

• a piston, an intake valve, and an exhaust valve for each cylinder, each being operatively coupled to the crankshaft;
• and a member rotatable with the crankshaft and having a detectable angular index, wherein the apparatus comprises:
• a crank angle reference determining sensor means responsive to the index of the rotatable member of an engine to be inspected and positioned to detect said index when a predetermined piston of the engine is in a top dead center position;
• a crank angle index device adapted to turn the crankshaft until the sensor means detects the index so as to place the predetermined piston in a top dead center position;
• displacement gauge means for simultaneously measuring the positions of a plurality of preselected valves when the sensor means detects the index;
• and
• crank angle indicator means connected to the displacement gauge means and responsive to the displacement values of the plurality of preselected valves for distinguishing whether the piston is in the compression top dead center position or in the exhaust top dead center position.