The role of the car distributor and the symptoms of a broken car distributor. What are the symptoms of a broken car distributor and how to find the root cause of the problem?
The role of the car distributor
The distributor is a component of the ignition system of a gasoline engine that distributes high-voltage current to the spark plugs of each cylinder according to the ignition sequence of the cylinders.
The function of the distributor in a car is to turn on and off the low-voltage electricity and distribute the high voltage generated by the ignition coil according to the ignition sequence of the engine to each cylinder spark plug. In the battery ignition system, the distributor and the igniter are usually installed on the same axis and driven by the camshaft. It also comes with devices such as ignition advance angle adjustment and capacitors. If it is damaged, precise ignition cannot be achieved, resulting in a decrease in engine efficiency or even failure to operate.
Symptoms of a broken car distributor
When the car distributor is broken, there may be no ignition, and the engine may not operate normally, making it difficult to start the car. Common fault symptoms include: starting difficulties; poor ignition; high-voltage leakage, etc. At the same time, the engine may experience symptoms such as knocking, shaking, poor acceleration, abnormal exhaust smoke, etc.
When the ignition switch is turned on and the engine is started, the ammeter swings between 3-5A, but there is no ignition sign on the engine, it indicates that there is a fault in the high-voltage coil or central high-voltage wire of the ignition coil, or there is a leakage fault in the capacitor. If there is no current or no change in current on the ammeter, it indicates a low-voltage circuit break.
When the ignition switch is turned on, use a test lamp to connect the movable contact arm of the breaker (at this time, the distributor cover should be removed to open the breaker contacts). If the lamp lights up, it indicates a breaker contact circuit breakage fault. Turn the crankshaft and observe whether the cam angle of the distributor shaft can push the breaker contacts open. If the breaker contacts cannot be pushed open, it indicates that the breaker gap adjustment is improper. If they can be pushed open, continue to check the gap of the breaker contacts and the contact condition of the working surface.
If the lamp does not light up, check if the capacitor has been short-circuited. If the capacitor is normal, continue to use the test lamp to connect the primary coil of the ignition coil. If the lamp lights up, check if there is an open circuit fault in the primary coil; if it does not light up, there is a fault in the ignition switch or the line between it and the positive terminal of the power supply.
Inspection method for the car distributor that is broken
In the storage battery ignition system, the distributor and igniter are usually installed on the same axis and driven by the camshaft. It also comes with devices for adjusting the ignition advance angle and capacitors. If it is damaged, precise ignition cannot be achieved, resulting in decreased engine efficiency or failure to operate. First, the ignition circuit was checked: The distributor cover was removed, and the movable contact arm was moved with a screwdriver to open and close the breaker contacts. It was found that the high-voltage spark was very strong. Then the distributor head was checked and it was also normal. Later, the carburetor circuit and fuel circuit were repeatedly checked. After reopening the distributor cover, the breaker contacts were checked and no serious ablation was found. It was not until the engine was turned over that it was found that the gap of the breaker contacts was too small. After adjustment, the engine was started again and the fault was eliminated.
When the engine is turning at low speeds, the contact closure time of the breaker contacts is longer, and the primary winding passes a larger current, which allows the capacitor to discharge normally, thereby ensuring sufficient ignition intensity.
However, when the engine speed increases, the opening and closing time of the breaker contacts will be shortened. Since the gap between the breaker contacts is too small, the capacitor voltage will be insufficient and may not function properly. Therefore, it cannot ensure sufficient ignition intensity, resulting in the engine not working properly or even stalling.
If the gap between the breaker contacts is too small, it will also cause the ignition time of the engine to be delayed, leading to an increase in engine temperature. As a result, a large amount of combustible mixture may be ignited in the exhaust pipe, causing the phenomenon of backfiring.
