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The device is preheating
On the diesel engine fuel is ignited in the highly compressed and therefore the hot air. During cold starts, the auto-ignition does not occur, as the auto-ignition temperature is reached. Glow plugs installed in the side of the settling chamber, creating the optimum ignition mode when the engine is cold. In direct injection engines warm-up time is significantly shorter. In addition, this device is mainly to reduce emissions. Operation of the preheating Preheating device consists of three main components: a glow plug of a core, the time switch and preheating warning lamp on the instrument panel. Glow plugs are designed for 15 V and connected in parallel. When you turn the ignition key after each spark current flows about 30 A. regulating winding in the glow plug reduces the current for about 10 seconds to 8-15 A. After 10 to spark reaches a temperature +900 ?� C after 30 - +1180 ?� FROM. Time relay plugs determines the length of the filament preheating. To this end, the relay has a sensor that measures the ambient temperature. At -30 ?� C preheating time of about 25 seconds at +20 ?� C - about 4 at +40 ?� C - about 2 seconds. If preheating is sufficient, the lamp control readiness of the engine goes out. If after the light goes out, the engine does not start, the fuse takes care of that in 20-25 with the current flowing through the spark has been disconnected. If during this time the engine is started, the device is connected again preheating during rotation starter. Glow plugs
| Fig. 4.92. Glow plugs Bosch-Duraterm
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This "core quick start glow plugs" (Fig. 4.92). The filament rod, which extends into a prechamber, located one behind the other and adjusting the heating coil. With increasing temperature, increasing the resistance of the windings. Thus, the current is reduced from 30 A to 8-12 A. Each glow plug is controlled separately by the microprocessor relays preheating time. Additionally, when using a small candle feed control current. Failure of one or more candles while the engine is signaled by a control lamp. When the engine starts, begin extra heating - it lasts up to 180 seconds until the coolant temperature reaches +40 ?� C. The meaning of the additional heater is to have a cold car to reduce excessive noise at start and improve exhaust. If the temperature sensor on the cylinder head is defective, the additional heating takes substantially 30 seconds. At high temperatures, the effect of which is constantly exposed to the candle, they can be damaged. Especially it affects the wrong spray nozzles, the injection pressure is too low or wrong injection timing. Time relays preheating
| Fig. 4.93. Time relays preheating
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This relay is installed in the engine at the left wing of the arch. If you remove the trim, you can see both slots. Time relay plugs (Fig. 4.93) heating the following functions: 1. The power switch controls the current bulbs. 2. Limitations on the magnitude of the current supplied through the use of a circuit breaker. 3. Turning off the warning lamp in the engine ready to run.
PRACTICAL ADVICE Faulty system preheating Faults preheating the models CDI can occur only when cold (below -10 ?� C). Only then can the system of direct injection is not easy to cope with starting the engine without the "support" of the heating system. System malfunction can be identified by a blue exhaust from the muffler. |
4. The fuse disconnects the filament current if the display remains on for 20-50 seconds (depending on ambient temperature). In the preheating system fault it indicates that the warning light does not illuminate when the ignition is switched.
Faults preheating If a cold engine does not start or is very bad, or when the ignition is switched on the dashboard does not light warning lamp preheating should identify and correct the problem. The search begins with a test light or creating bridges on certain electrical circuits. Various testing begins with two jacks on the relay preheating time, are easy to find, removing the cover. When you turn on the heating control lamp does not light, there may be the following faults. 1. No current to the terminal "30" time relay preheating. 2. Defective power relay. 3. Defective one or more wires at the spark plugs. 4. Blown one or more glow. 5. Burnt-out indicator lamp, or its connecting cable is damaged.
Failure warning lamp If the warning light does not come on, despite the fact that the engine runs well, then, maybe it burned.
| Fig. 4.94. Check the operation of a control lamp preheating device: 1 - preheating time relay; 2 - plug the temperature sensor and a control lamp; 3 - a control lamp; 4 - plug glow plugs; 5 - terminal to connect a control lamp "in the mass"
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1. Remove the small plug on the relay preheating time 1 (Fig. 4.94). 2. Turn on the ignition. 3. Nest "3" connector to connect to "weight". Now, the test lamp should light up. 4. If not - check the wiring to the dashboard or replace the lamp.
Voltage monitoring relay time preheating If the engine does not start and the control lamp preheating, check the power switch of the preheating time. 1. Red wire should always be energized (terminal 30). 2. With the ignition on terminal "15" to be "+". Check the slot 1 on a smaller connector. 3. When a starter is rotated, the terminal "50" should also be a current (slot 2).
Check current supply to the glow plug After ignition current must be applied to all glow. 1. Disconnect the large connector to the device preheating. 2. Connect the test lamp to the "masses." 3. Check the current one after the other on all the relay contacts. After ignition on each contract at the time of ignition should be "+". When checking the assistant should turn on and off the ignition, all the time was the preview bulbs. If there is a current of the relay, replace the relay.
Disclaimer glow If the test lamp does not illuminate, perhaps burned one of the glow plugs. If the engine is started, at first it does not work on all cylinders. In the cylinder without preheating somewhat later self-ignition occurs. 1. To detect the candle burned down a large disconnect the plug from the timer.
| Fig. 4.95. Detection of a faulty candle: 1 - "mass"; 2 - terminal control lamp; 3 - in the plug socket
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2. Connect the test lamp on one end of the "+" (for example, to the red wire) (Fig. 4.95). 3. The other end of the lamp, one by one check in the plug socket. 4. Where the warning light does not lit, faulty spark plugs.
PRACTICAL ADVICE Faulty spark 1. If you do not have to check a control lamp, you can check out the candle on the "spark". 2. Remove the power plug to the device and the preheating of the wire "+" check one by one slot. Where there is no spark plug is faulty. 3. If the system does not work preheating, you can start the engine in tow. The engine may start after 1 km. Try to tow start the engine revving the engine, such as the 2nd gear from 40 km / h (follow carefully!). 4. If the time switch has switched off while driving, stop all the wires to the spark connect together and connect with the 10-20 to the "+". |
Replacing the glow plugs 1. To get to the glow plugs, which are located on the left side in the cylinder head, it is necessary key- "rattle" with various heads, nozzles.
| Fig. 4.96. Location glow: 1 - glow plug with a plug; 2 - the fuel valve on the heat exchanger; 3 - heat exchanger; 4 - nozzle
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3. Remove the spark plug. 4. Place a new spark plug and torque to 20 Nm.
Check glow plugs The only and most reliable way to check the glow plugs - from inside-out. 1. If necessary, remove the engine cover. 2. Disconnect the spark plug. 3. Remove the candles and put on a fireproof surface. 4. One by one, the candles connect using thick wire (minimum 2.5 mm2) and reliable terminals directly to the battery. 5. Check to see what little spark (there are too), and which does not spark. 6. Replace the malfunctioning spark. If you want to be absolutely sure the candles, you can replace the entire set.
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