CAUTION: The following procedure is based on the assumption that the high voltage wires of the spark plugs and ignition distributor (if there) installed properly. If you are trying to determine the TDC for a proper distributor setting, the piston position can be determined by feeling compression in the spark plug hole of number one cylinder, and then aligning the ignition timing marks.
top dead center (TDC) called the highest position in the cylinder that each piston reaches in the process of moving up and down as the crankshaft rotates. Each piston reaches TDC on the compression cycle and then again on the exhaust cycle, but usually TDC refers to the position of the piston during the compression cycle.
Setting the piston to TDC is an important part of many processes, such as removing the camshaft and drive belt or removing the ignition distributor (if there).
Before starting the process, make sure that the transmission (Transmission) was in the neutral position Apply the handbrake or block the rear wheels. Turn off the ignition system by disconnecting the coil high voltage wire from the center terminal of the distributor cap/diagnostic connector and ground it to the unit using the auxiliary wire. Remove the spark plugs.
To set the piston to TDC, rotate the crankshaft using one of the methods described below.
CAUTION: Looking at the front of the engine, the crankshaft should rotate normally in a clockwise direction.
The most preferred method of turning the crankshaft is to use a ring wrench.
If you can use the help of an assistant who will turn the ignition key to position «start» for short periods of time, it is quite possible to bring the piston closer to the position.
Make sure the assistant is out of the car and not touching the ignition, then use the key.
Mark the position of the contact for the high voltage passage of the spark plug of the first cylinder on the distributor cap. If this contact is not marked, trace the wire path from the spark plug of the first cylinder to the distributor cap.
Mark the distributor body directly below the contact.
Detach the cap from the distributor and place it aside.
Locate the marks on the front cover You will see the marks directly above the crankshaft pulley. Turn the crankshaft so that the mark on the front cover matches the mark on the pulley.
After the piston of the first cylinder has been set to the TDC position of the compression cycle, the TDC position for the remaining cylinders can be determined by turning the crankshaft and following the firing order.