The location of the top dead center (TDC) of the piston No. 1

1. Top dead center (TDC) - the highest point in the cylinder that the piston reaches, moving back and forth as the crankshaft rotates. Each piston reaches TDC twice - on the compression and exhaust strokes, but usually TDC is spoken of when the piston is in the compression stroke. flywheel marks (cars with manual transmission) or on the drive plate (for cars with automatic transmission) refer to the position of #1 piston at TDC on the compression stroke.

2. Piston installation (-her) at TDC - an important part of many procedures such as removing valve levers, replacing the ignition chain and sprocket, removing the distributor.

3. Before starting the procedure, make sure that the coil wire is removed from the distributor cap and ground it. not to damage the coil (chapter 5).

4. To bring the piston to TDC, turn the crankshaft in one of the ways described below. Looking at the front of the engine (from the passenger seat in the car) normal rotation of the crankshaft should be clockwise.

Warning: Make sure the transmission is in neutral before starting work.

The preferred method is to turn the crankshaft using a large socket and wrench, with a pulley bolt screwed into the front of the crankshaft.

5. Note the location of the #1 spark plug socket on the distributor cap (it is marked 1) (cm/ figure). Use chalk or a marker to make a mark on the dispenser just below the socket. Unscrew the fasteners, disconnect the cover from the distributor and set aside.



6. Rotate the crankshaft until the triangular notch on the flywheel/drive bar aligns with the stationary pointer 8 in the bell-shaped viewing window (cm/ figure).

Note: although the 5-degree VTDS mark on the flywheel (Manual Transmission) and triangular notch (5 - percent mark of VTDS) on the drive plate (Automatic transmission) is actually designed to adjust the ignition, they can be used to bring the No. 1 piston to TDC.

7. Take a look at the distributor slider - it should be directed to the mark you made on the distributor body (cm/ figure). If the rotor is pointing at spark plug seat #4 (away from the engine), then piston #1 is at TDC on the exhaust stroke.



8. To set the piston to TDC on the compression stroke, rotate the crankshaft a full turn (360 degrees) clockwise. The slider will point to the mark on the distributor. When the slider points to the #1 spark plug wire socket and the spark marks match, the #1 piston is at TDC on the compression stroke.

9. After piston #1 is set to TDC on the compression stroke, the TDC for the remaining cylinders can be determined by rotating the crankshaft 180 degrees in firing order (1-3-4-2).