A non-contact shielded ignition system is installed on the ZIL-1Z1 vehicle and its modifications
Scheme of the ignition system is shown in fig. 1.
The system consists of a B118 ignition coil, a 4902.3706 distribution sensor, a TK200-01 transistor switch, SN-307V spark plugs, high voltage wires in shielding hoses and manifolds, a VKZ50 ignition switch and an additional SEZ26 resistor, which automatically short-circuits when the engine is started.
To protect radio reception from interference generated by the ignition system, an FR82F radio interference suppression filter is included in the power circuit of the ignition system.
B118 ignition coil (Fig. 2) shielded, sealed. Unlike other ignition coils, one end of the secondary winding is internally connected to the coil body.
An additional resistor ( fig 3) unshielded, designed to limit the electric current flowing in the circuits of the ignition system in operating and emergency modes.
The nichrome coil 3 is mounted on a porcelain insulator 4 in a stamped metal case 5.
The ends of the spiral are connected to output terminals 1, mounted on insulating bushings 2, installed in the metal bottom of the housing.
When replacing the coil, the additional resistor is removed from the car.
Transistor switch is designed to switch the electric current in the primary winding of the ignition coil (breaking the primary circuit of the ignition coil at the right time by turning on the high ohmic resistance of the output transistor)
The transistor switch is installed on the left wall in the cab of the car and can only work at an ambient temperature of no higher than 70˚ C and no lower than minus 60° C.
It is not repaired under operating conditions and is replaced in case of failure.
To test the functionality of the switch on the stand, it is necessary to assemble a circuit for a contactless ignition system (Fig. 1▲)
By turning on the supply voltage (12.6 ± 0.6) V and changing the speed of the distribution sensor from 20 to 1600 min-1, one can observe stable sparking on the arresters.
When using a generator, instead of a sensor, a sinusoidal output voltage with an amplitude of 2 - 10 V is set on the generator and, by changing the generator speed from 2.6 to 213 Hz, one can observe stable sparking on the spark gap connected directly to the ignition coil.
Absence of sparking indicates a faulty switch that needs to be replaced.
The switch protection against an emergency increase in supply voltage occurs at a frequency of rotation of the distributor shaft of 1000 min-1 or a generator signal frequency of 135 Hz by smoothly increasing the supply voltage until the sparking completely stops, but not more than 23 B.
When checking the operability of the contactless ignition system devices on a car, it is necessary to remove the cover of the sensor-distributor screen, pull out the high-voltage wire from the central socket of the distributor cover; having set the gap between the end of the high-voltage wire tip and the distributor screen housing 4 - 6 mm, turn on the ignition, and turn the crankshaft with a starter or crank with a speed of at least 40 min-1.
The presence of a spark discharge in the gap indicates the health of the ignition system as a whole.
If there is no spark in the gap, disconnect the low-voltage connector from the sensor that goes to the "D" input of the switch, and touch the connector plug to any point in the vehicle's on-board network that is energized at 12 V (the output of the additional resistor, the "+" output of the battery batteries).
The presence of a spark in the gap between the end of the tip of the high-voltage wire and the screen housing indicates a malfunction of the distribution sensor, and the absence of a spark indicates a malfunction of other devices.
Sensor-distributor (see Fig. 4) shielded, works in conjunction with the ignition coil B118, designed to control the operation of the switch, the distribution of pulses high voltage on the engine cylinders in the required sequence, to automatically adjust the ignition timing depending on the crankshaft speed, as well as to set the initial ignition timing.
Removing the distributor sensor from the engine
There are two ways to remove the distributor sensor from the engine:
- - disconnect the fastening of the brackets of the spark plug wires by unscrewing these wires from the spark plugs, disconnect the wires of the low-voltage and high-voltage terminals on the distributor sensor and, having unscrewed the two bolts securing the distributor sensor to the block, remove it from the engine along with the spark plug wires and their brackets,
- — unscrew the low-voltage and high-voltage wires from the terminals of the distribution sensor, unscrew the bolts (see Fig. 4) and remove the cover 8 of the screen.
Then, remove the spark plug wire of the distributor sensor and, unscrew the bolt 20 for fastening the adjusting plates, remove the distributor sensor from the engine.
Be careful not to drop bolt 20 and washers into the engine.
Disassembly of the ignition distributor sensor
To disassemble the ignition distributor sensor, it is necessary to fix it in a vice on the body 16 and, having unscrewed the screen fastening bolt 9 to the body, protect the rubber sealing rings from falling out or damage.
Remove the cover 10 and slider 11, unscrew the two screws 15 and remove the stator assembly using a bit or unscrew it.
Using a beard, knock out pin 23 from roller 3, remove sleeve 24 complete with washer and remove roller 3 complete with centrifugal governor and rotor 14.
After that, remove the support bearing 25 with the plate from the housing 16.
To remove the rotor 14 from the roller, you need to remove the felt 28 and unscrew the screw 27.
Regulator spring 26 is easily removed from the posts using pliers or a screwdriver.
Checking the details of the distribution sensor
After disassembly, all parts of the distribution sensor must be washed with kerosene or gasoline and wiped dry with a napkin.
After that, they must be carefully examined.
On the cover 10 of the distributor, cracks, chips, burnouts of high-voltage terminals and other defects are not allowed.
It is necessary to check the freedom of movement of the coal in the nest, the cover and replace it if it is heavily worn.
Then it is necessary to check the play of the roller 3 in the housing 16 and, if any, press out two bushings 29, replacing them. If springs 26 are defective, they must also be replaced.
To check the operability of rotor 14, a tester or a test lamp with a battery must be connected to the winding terminal and to the low-voltage output plate and determine the absence of a winding break.
If there is a winding break, the rotor must be replaced.
Distributor sensor assembly
Before assembling, lubricate the surface of roller 3 with engine oil, install rotor 14 on it and secure with screw 27.
Then put 2-3 drops of engine oil on screw 27 and put filter 28 in the hole of the rotor.
Install, if they were removed, springs 26 on plastic racks.
next, install support bearing 25 into housing 16, lubricating it and the support washer mounted on top of it with Litol-24 grease.
Then, insert roller 3 complete with rotor into housing 16, put washer and bushing 24 on its lower end and install pin 23 into the hole on the roller, unfastening it with a core.
Install stator 13 into housing 16, placing it with terminals with wires up.
At the same time, after wiping the low-voltage terminal plate with alcohol, place it opposite terminal 4 of the housing 16. Fasten the stator with two screws 15.
Install slider 11 on the roller and close the distributor with cover 10, aligning the grooves in the cover and body 16.
After checking the presence of rubber sealing rings in the housing 16, install the screen 9 on the housing and fix it with bolts 19. After that, fill the oiler 2 with Litol-24 grease.
When assembling terminal 4, it is necessary that wire 7 is soldered to terminal 9, and the shielding braid 1 is well threaded and clamped with washers 4 and 5.
In order to check the operability of the distribution sensor, it must be installed on a test bench and tested.
- — characteristics of the centrifugal machine;
- is the maximum voltage at the low voltage input, which should be 45 V at a roller speed of 1600 min-1.
The distribution sensor must provide an output voltage amplitude value close to sinusoidal, not less than 1.4 V at a load equivalent of 3.9 kOhm at a roller speed of 20 min-1.
Installing the ignition distributor sensor on the engine
The ignition distributor sensor is installed on the engine in the reverse order of its dismantling.
The crankshaft pulley mark must match the mark 9 on the ignition timing indicator.