Note. The following procedure assumes that the ignition distributor is installed correctly. If you need to set the TDC to install the distributor, the position of the piston can be determined by plugging the spark plug hole of cylinder No. 1 with your finger, by changing the pressure in the cylinder. Then, more accurately, you can set the TDC according to the marks on the crankshaft pulley.
1. Top dead center (TDC) - the uppermost position of the piston in the cylinder, which it can occupy when the crankshaft rotates. In a four-stroke engine, each piston goes to TDC twice during the operating cycle - at the end of the compression stroke and at the end of the exhaust stroke. It usually has a TDC value on the compression stroke,
2. The installation of pistons in the V MT is necessary when performing many repair and adjustment work, such as removing and installing parts of the gas distribution and ignition mechanism.
3. Before starting this operation, set the transmission to neutral and block the rear wheels, for example, by applying the handbrake. Also turn off the ignition system by disconnecting the low voltage wires from the ignition coil (see chapter 5). Also remove the spark plugs (see chapter 1) and turn off the fuel supply system (see chapter 4).
4. To set any piston to TDC, turn the crankshaft in one of the following ways. The normal direction of rotation of the crankshaft is clockwise when viewed from the pulley side of the engine.
- A) The most common way to rotate the shaft is with a socket wrench, put on a socket bolt screwed into the toe of the crankshaft.
- b) You can use the remote starter switch. If you have such a switch, use it in accordance with the manufacturer's instructions. Bring the crankshaft close to the TDC position, then tighten it with a wrench, as described above.
- b) You can ask an assistant to turn on the starter with the ignition key in short pulses. In this way, you can check the crankshaft close enough to the TDC position, and then tighten it using the (A). At the same time, make sure that the assistant removes the ignition key from the lock and leaves the car.
1997 and earlier models
5. Find an output on a cover of the distributor of ignition. corresponding to cylinder #1. If the leads on the cap are not marked, trace the high voltage wire from the spark plug to the cap.
6. Mark with a felt-tip pen or chalk the cover and the distributor body opposite the output No. 1.
7. Remove the cap from the distributor and set it aside (if necessary see chapter 1).
8. Rotate the crankshaft until the notch on its pulley matches the TDC mark on the timing dial (pic. 3.8).
9. Look at the ignition gel distributor rotor. It should point exactly at the mark you made on the case.
10. If the rotor is rotated 180°relative to the mark, then piston No. 1, although it is at TDC, is finishing the exhaust stroke.
11. In order to bring piston No. 1 to TDC on the 8th compression stroke, turn the crankshaft a full turn (360°) clockwise. Now the distributor rotor should turn to the side of the mark. If the distributor rotor points to the output of spark plug No. 1, and the mark on the crankshaft pulley matches the pointer. So piston #1 is at TDC on the compression stroke.
Note. If the distributor rotor is directed towards the contact of spark plug No. 1, and the marks on the crankshaft pulley do not match, then the camshaft drive belt is not installed correctly.
Release models since 1998
12. Models since 1998 are equipped with a distributorless ignition system (see chapter 5). To install piston No. 1 at TDC, unscrew the spark plug from cylinder No. 1 and screw a compression gauge into the hole from under the spark plug.
13. Turn the crankshaft (see item 4 of this paragraph). As the piston approaches TDC on the compression stroke, the pressure recorded by the compression gauge will begin to increase. Continue turning the crankshaft until the pointer on the crankshaft pulley aligns with the TDC mark (see fig. 3.8). After the pressure starts to rise, do not turn the crankshaft more than necessary to align the marks.
14. It may take up to two full revolutions of the crankshaft to set the piston to TDC on the compression stroke. If during the first revolution the pressure does not begin to rise, continue to rotate the crankshaft. If there is pressure and the marks match, then piston No. 1 is set to the desired position.
All models
15. After the torus and as the piston No. 1 is set to TDC on the compression stroke, the remaining pistons can also be set to TDC by turning the crankshaft in 180°portions and following the order of operation of the cylinders (those. an additional 180°turn will bring #3 piston to TDC, etc.).