Distributor
Before installing the ignition distributor on the stand, check the condition of the breaker contacts, whether the lever with the movable contact is sticking, as well as the pressing force of the contacts, which should be 500-600 gf. Check the wear of the pads of the breaker lever, in case of wear, set the required gap between the contacts of the breaker.
If the contacts of the breaker are dirty, burnt or eroded, then they are cleaned with a needle file. Grinding paper and other abrasive materials cannot be used for this purpose. After stripping, wipe the contacts of the breaker with suede soaked in gasoline. Then the lever is pulled back so that the gasoline evaporates, and the contacts are wiped again with dry suede. Instead of suede, you can use any material that does not leave fibers.
Contacts must be in contact with the entire surface. If this does not happen, then, bending the rack bracket, adjust the position of the fixed contact. It is impossible to bend the lever with a movable contact. Wipe the cover of the ignition distributor from dirt and oil. Slightly lifting the cover of the ignition distributor, check whether the contact of the rotor is against the electrode of the cover at the moment the breaker contacts are opened.
Checking work
Install the ignition distributor on the test stand for checking electrical appliances and connect it to the electric motor, the speed of which is adjustable. Make connections to the ignition coil and to the battery. Four terminals of the cover are connected on the stand with spark gaps, the gap between the electrodes of which is adjustable.
A gap of 5 mm is set between the electrodes of the arresters, the electric motor of the stand is turned on, and the distributor roller is rotated for several minutes clockwise at a frequency of 2000 rpm.
Then the gap between the electrodes is increased to 10 mm and they monitor for internal discharges in the ignition distributor, which are detected by sound or by the weakening and interruption of sparking on the spark gap of the test bench.
During operation, the ignition distributor should not produce significant noise at any speed of the roller.
Removal of characteristics of the centrifugal regulator of an advancing of ignition
Install the ignition timing controller on the stand and make electrical connections in accordance with the instructions for the stand. The stand electric motor is turned on and the ignition distributor shaft is rotated at a frequency of 300-400 rpm for P125 distributors and 150-200 rpm for distributors 30.3706-01. On a graduated disk, a value in degrees is counted, according to which one of the four sparks is obtained.
Increasing the rotational speed and making readings at each increase by 200-300 rpm, determine the number of degrees of ignition advance relative to the initial value, depending on the rotational speed of the ignition distributor roller. The obtained characteristic is compared with the characteristic in fig. 166. If the characteristics do not match, then select new weight springs or replace the distributor.
Checking the angle of the closed state of the contacts
Install the ignition distributor on the test bench and remove the cover from it. Perform connections in accordance with the instructions for the stand. Turn on the electric motor of the stand and bring the rotational speed of the ignition distributor roller to 1000 rpm. On the scale of the stand, measure the angle of the closed state of the contacts, which should be (55±3) °. After checking the angle of the closed state of the contacts, the angles between the moments of opening the contacts in the cylinders relative to the first (asynchronism), which should not differ from the nominal by more than 1°.
Insulation resistance test
The insulation resistance between the various terminals and ground must be checked with a megohmmeter. Resistance between the low voltage terminal of the breaker and "weight" measured with open breaker contacts. Insulation resistance at (25±5) °С must be at least 10 mΩ.
Capacitor check
Capacitor capacitance, measured in the frequency range between 50 and 1000 Hz, should be in the range of 0.20-0.25 µF.
Removal of characteristics of the vacuum regulator
Install the ignition distributor on the stand and make connections in accordance with the instructions for the stand. The stand electric motor is turned on and the ignition distributor shaft is rotated at a frequency of 1000 rpm. On a graduated disk, a conditional is set "zero" by the moment of sparking in any of the cylinders.
Gradually increasing the vacuum, every 20 mm Hg. Art. note the number of degrees of ignition advance relative to the initial value. The resulting characteristic is compared with the characteristic in Fig. 167. Regulate the characteristics of the vacuum regulator by selecting shims between the spring and the plug of the vacuum regulator. When taking the characteristic, it is necessary to pay attention to the clarity of the return to the initial position of the movable breaker plate after the vacuum is removed.
Ignition coil
At the ignition coil, the ohmic resistance of the windings is checked, which at 20°C should be 3.07-3.5 ohms for the primary, and 5400-9200 ohms for the secondary. Then check the reliability of the insulation for "mass". The ignition coil shall be capable of withstanding 1500 V AC applied for 1 minute between one end of the primary and the case. Insulation resistance on "mass" must be greater than or equal to 50 MΩ.
Spark plug
If there are interruptions in ignition, especially in one or more cylinders, it is necessary to check the condition of the candles. Before testing, spark plugs with carbon deposits or contaminated ones are cleaned in a special installation with a jet of sand and blown with compressed air. If the soot is light brown in color, then it can not be removed, since it appears on a working engine and does not disrupt the operation of the ignition system.
After cleaning, inspect the candles and adjust the gap between the electrodes. If there are chips, cracks on the spark plug insulator, or the side electrode welding is damaged, then the spark plug is replaced. Gap (0.5—0.6 mm) between the electrodes, the candles are checked with a round wire probe from the tool kit applied to the car. It is impossible to check the gap with a flat probe, since this does not take into account the recess on the side electrode, which is formed during the operation of the candle. The gap is adjusted by bending only the side electrode of the spark plug. The central electrode is not bent, as this can cause breakage of the ceramic insulator.
Leak test
A candle is screwed into the corresponding socket on the stand, and then a pressure of 20 kgf / cm 2 is created in the stand chamber2. Drop a few drops of oil or kerosene on the candle. If the tightness is broken, then air bubbles will usually come out between the insulator and the metal body of the candle.
Electrical test
Adjusting the gap between the spark plug electrodes (0.5—0.6 mm), screw it into the socket on the stand and tighten it with a torque wrench to a torque of 3.2-4 kg-m. Tightness is ensured by an elastic gasket of the socket fitting. The gap between the electrodes of the arrester is adjusted by 12 mm, which corresponds to a voltage of 18 kV, and then a pressure of 6 kgf/cm is created by the pump2. Install the tip of the high voltage wire on the candle and press the switch button. In this case, the following may be observed.
1. A full-fledged spark between the electrodes of the candle is visible in the eyepiece of the stand. In this case, the candle is considered serviceable. In this case, several sparks are allowed on the arrester.
2. Sparking occurs between the electrodes of the arrester. In this case, you should lower the pressure in the device and check at what pressure sparking occurs between the spark plug electrodes. If at a pressure of 5 kgf / cm2, then the candle is considered normal, and if at a pressure of 4 kgf / cm2 and below - defective.
If there is no sparking on the spark plug and on the spark gap, it must be assumed that there are cracks on the spark plug insulator and that the discharge occurs internally between the mass and the electrodes. Such a candle is considered defective.
Ignition switch
At the ignition switch, the operation of the anti-theft device is checked and the correct closure of the contacts at various key positions (tab. 27). Voltage from the battery and generator is supplied to the contacts "30" And "30/1". Contacts "16" switches are not used. free plug "INT" designed to connect a radio receiver, Since 1986, a contact part has been installed, in which the contact "16" absent.
The locking rod of the anti-theft device must extend when the key is set to the position "Parking" and take it out of the castle. The rod should move in after turning the key from the position "Parking" into position "Turned off".
When installing the contact part in the circuit breaker housing, it must be positioned so that the plugs "15" And "30" were on the side of the locking rod. Then the wide protrusion of the contact part will fit into the wide groove of the switch body.
Elements for suppression of radio interference
These elements include high voltage wires with a resistance distributed along the length (2000±200) Ohm/m and interference suppression resistor in the rotor of the ignition distributor with a resistance of 5000-6000 Ohm,
The performance of these elements is checked with an ohmmeter.