Timing Components: Testing and Inspection

When the pistons in No.1 and No.4 cylinder are at top dead center, the 0° mark on the crankshaft pulley should be in line with the mark on the timing cover (or the 0° mark on the flywheel/drive plate should be in line with the mark on the end plate).

When the timing marks on the camshaft are in line with those on the bearing caps, the inlet and exhaust valves for No.1 cylinder are closed.

As the valve opens,they extend beyond the face of the cylinder head and into the zone where the pistons change direction.

As will be realized, if the setting of the crankshaft and valve gear is altered, the valves and other vital parts of the engine will be damaged.