What are the symptoms of engine ignition being too early or too late?

[ArabellaMarie]

The symptoms of engine ignition being too early or too late are as follows: 1. Ignition too early: When hand-cranking the engine, the crankshaft may reverse; when using the starter, the starting resistance is high, making the engine difficult to turn over; after starting, during acceleration, the engine may produce severe knocking sounds. 2. Ignition too late: The engine feels sluggish and lacks power, and the temperature tends to rise; acceleration is difficult, and high-speed operation is uneven; the exhaust pipe emits black smoke, sometimes backfires, and the carburetor may also backfire; starting resistance is low, but the engine is hard to start. Here are the troubleshooting methods for ignition being too early or too late: 1. Too early: Remove the distributor cap, check if the breaker point gap is too large, and adjust it to 0.4-0.5 mm. Loosen the distributor housing positioning screw and rotate the distributor clockwise until the knocking sound disappears during acceleration. 2. Too late: Open the distributor cap, check if the breaker point gap is too small, and adjust it to 0.4-0.5 mm; loosen the distributor fixing screw and rotate the distributor counterclockwise until the engine speed increases rapidly during acceleration.