Timing Light‑Free Adjustment Method
① First, adjust the distributor contact gap to the specified standard value.
② Locate the compression top dead center (TDC) of the No.1 cylinder. Remove the high‑tension distributor cable of the No.1 cylinder. Unscrew the No.1 spark plug with a spark plug socket, block the spark plug hole with your thumb or a cloth bundle, then crank the engine crankshaft. When feeling cylinder compression resistance, rotate the crankshaft slowly and align the timing marks precisely.
③ After completing the above preparations, turn on the ignition switch, loosen the distributor housing fixing bolt, and rotate the distributor housing to close the breaker contacts. Then turn the distributor counterclockwise until the contacts just start to open; a tiny spark will be generated between the contacts at this moment. Tighten the distributor housing fixing bolt and set the octane adjuster to the zero scale position. At this point, the direction pointed by the rotor corresponds to the No.1 cylinder position.
④ Install the high‑tension cables on the distributor cap in the correct firing order, tighten the bolts by hand to temporarily fix the distributor.
⑤ Start the engine to check the ignition timing. If the ignition system and fuel supply system are properly adjusted, water should drip from the exhaust pipe, with minimum engine vibration and noise.

Timing Light Adjustment Method
① Start the engine and warm it up to normal operating temperature.
② Connect the two black clamps of the timing light to the positive and negative battery terminals respectively, and clip the sensor onto the high‑tension lead of the No.1 cylinder.
③ Let the engine run at normal idle speed. Aim the timing light at the timing pulley, and check whether the timing mark aligns with the manufacturer’s specified angle (generally 6°～10°).
④ If adjustment is needed, loosen the distributor fixing bolt. Keep the timing light aimed at the timing pulley, rotate the distributor left or right until the scale mark reaches the specified value, then fully tighten the distributor bolt.