Pic. 7-19. The location of the marks for setting the ignition: 1 - ignition advance mark by 10°; 2 - ignition advance mark by 5°; 3 - ignition advance mark by 0°; 4 - mark w.m.t. on the crankshaft pulley
You can check and set the ignition timing using a stroboscope in the following order:
- set the eccentric of the octane corrector of the ignition distributor to the zero position (if the ignition distributor R-125 V is installed on the engine),
- connect clamp «+» strobe with terminal «+B» ignition coils, and clamp «masses» with terminal «-» battery;
- insert an adapter for connecting a strobe lamp between the spark plug wire of the first cylinder and the spark plug and mark mark 4 on the crankshaft pulley with chalk for greater visibility;
- start the engine by directing the flashing stream of strobe light at the mark on the pulley; if the ignition timing is set correctly, when the engine is idling, mark 4 visible on the pulley should be against mark 2 on the timing cover.
To adjust the ignition timing, stop the engine, loosen the distributor mounting nut and turn it to the desired angle. To increase the ignition timing, the distributor housing should be turned counterclockwise, and to decrease it, clockwise. Then check the ignition timing again.
If there is a diagnostic stand with an oscilloscope, then it can also be used to easily check the ignition timing setting, acting as described in the instructions for the stand.
Install the ignition distributor removed from the engine in the following order:
- remove the cover from the distributor, check and, if necessary, adjust the gap between the breaker contacts;
- turn the crankshaft until the start of the compression stroke in the first cylinder, and then continuing to turn the crankshaft, align mark 4 with mark 2;
- turn the rotor in such a position that its outer contact is directed towards the contact of the first cylinder on the distributor cap;
- while holding the distributor shaft from turning, insert it into the socket on the cylinder block so that the center line passing through the spring latches is approximately parallel to the engine center line;
- fasten the distributor to the cylinder block, install the cover, connect the wires, check and adjust the ignition setting.