Check that the ignition is off Remove the high-tension wires from the spark plugs, then unscrew the spark plugs.
Turn the engine with a wrench, by the crankshaft pulleys, until the timing mark on the crankshaft pulley aligns with the TDC mark (0) on the timing mechanism cover. As the mark on the pulley approaches, the piston of cylinder No.1 simultaneously approaches the top of the cylinder (see Fig. 2A.2).
You can check that the piston is in the compression stroke by removing the cylinder head cover and observing the movement of the valves.
After aligning the timing marks on the crankshaft pulley and timing cover, rock the crankshaft back and forth a few degrees either side of this position and observe the valve action for cylinder #1. When the piston of cylinder #1 is at TDC, the intake and exhaust valves of cylinder #1 will be completely closed, but the corresponding valves of cylinder #4 will be in the open and closed positions. If the valves of cylinders #1 and #4 are in the exact opposite positions, it is necessary to rotate the crankshaft one full revolution so that the piston of cylinder #1 is at TDC on the compression stroke.
After setting the piston of the first cylinder to TDC in the compression stroke, you can sequentially set any other piston to TDC in the compression stroke by turning the crankshaft clockwise by 180° and taking into account the order of operation of the cylinders.