Attention! It is assumed that the work is carried out with the ignition distributor correctly installed (on 3.0 l engines). If it is necessary to restore the correct position of the distributor, then determine the engine stroke by feeling the compression in the 1st cylinder with the spark plug removed, then align the ignition timing marks (see below).
Setting the piston of the 1st cylinder to TDC of the compression stroke is necessary to perform adjustment and setup work (valve adjustment, ignition timing, etc.).
1. Move the transmission control lever to neutral. Eliminate the possibility of ignition by grounding the center wire of the distributor (3.0 L) or by disconnecting the connector on each of the 3 ignition coils (3.4 L). It should be noted that the crankshaft should only be turned clockwise.
Installation procedure for 3.0L engines
2. Mark the spark plug terminal of the 1st cylinder with a mark on the distributor housing.
3. Remove the distributor cap..
4. Turn the crankshaft clockwise until the mark on the crankshaft pulley aligns with the "0" mark on the fixed scale.
5. If the distributor runner pointer is opposite the mark on the distributor housing, then the piston of the 1st cylinder is at TDC of the compression stroke. If the runner is turned 180° from the mark, then turn the crankshaft by 1 revolution, after which the piston of the 1st cylinder will be set at TDC of the compression stroke. In this case, the marks on the scale and pulley should be aligned, and the runner pointer should be opposite the mark indicating the output of the 1st cylinder.
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6. Mark the terminals of the other wires in accordance with the engine operating order. By turning the crankshaft further clockwise relative to the TDC position of the 1st cylinder, you can set the piston of each cylinder to TDC by aligning the runner pointer with the terminal marks.
Installation procedure for 3.4L engines
7. Remove the spark plug of the 1st cylinder and connect the compression gauge through a hose approximately 150 mm long, screwing the hose fitting into the spark plug hole.
8. Turn the crankshaft until the compression pressure begins to increase as the marks on the pulley and the scale approach each other. Once past the marks, remove the gauge and turn the crankshaft 2 more revolutions.
Attention! The most accurate setting of the piston at TDC of the compression stroke on such engines is achieved by simultaneously aligning the marks on the crankshaft pulley and on the camshaft sprockets (see subsection 3.1.7).