Tips and tricks

Truck starter

Starter - mount instruction.

Aternator - mount instructions.

Stanowisko do regeneracji włączników elektromagnetycznych i bendiksów.

SOLENOID - OPENER/CLOSER

FILM INSTRUKTAŻOWY - DEMONTAŻ I MONTAŻ STOJANA ALTERNATORA

To answer the question whether the alternator works correctly you just need to use any working instrument of appropriate measurement range, designed for measuring constant voltage and take a number of simple measurements.

We propose to follow the procedure described below:

• Without switching the engine on, connect the measurement instrument to the battery, as shown on Fig. 1, measure the voltage and remember the voltmeter reading
• Start the engine and watch if the battery charge indicator light goes off.  Continue the testing even if it doesn’t.
• Let the engine work for two minutes without energizing the load.  We recommend the delay since in some of the recently constructed cars the alternator does not switch on instantly after the indicator light goes off.
• Measure the voltage on the battery clamp again.  The measured voltage without any load energized and at slow revolution should be more than 13 V.  
• Compare the reading with the previous one.  An increase in voltage indicates the battery is charging.  It is not, however, a sufficient basis to assess whether the alternator works correctly.
• Turn on the defogger setting its speed to the maximum and switch on the rear window defroster, while keeping the engine at about 2000 RPM (approximately two times more than on idle speed). 
• Measure the battery voltage again. If the alternator works correctly, the voltage should be at least 13.5V.

Once the indicator light has gone off and the measured voltage is as required above, you may conclude the alternator is working correctly. If the voltage is not as required or the indicator light is still on, you may assume the alternator works incorrectly. If you want to try to diagnose the causes of alternator malfunction, it is worthwhile to perform additional procedures and take extra measurements:

• Check whether the working alternator emits abnormal buzzing caused by damaged rectifying diodes or produces loud working noise because of a damaged bearing
• Check if the driver belt is sufficiently tensioned. If it is too loose, the alternator will not reach the full current capacity
• Check whether the rotations of the alternator rotor correspond with the rotations of the alternator belt pulley (applies to alternators with overrunning pulley - the so-called freewheeling alternators). In some damages to the pulley, the alternator rotor is not driven even if the pulley rotates.
• Take an additional measurement directly on the alternator clamps, as shown on Fig. 4. Compare the reading with the alternator voltage.  If the car electric installation is working property, the difference in the voltmeter readings should not exceed 0.1V.  Any difference in the measured values above that threshold indicates the installation is defective (poor quality of clamps on battery terminals, no ground to the engine shell, incorrectly connected alternator, etc.).

Based on the measurements taken and indications of the indicator light you can tentatively identify the underlying cause of the alternator’s incorrect operation.  This will help you make appropriate decisions and remove the defect. The table listing the symptoms versus their potential causes may prove helpful when diagnosing the problem. 

Electromagnetic switches trigger connection between the starter motor and the battery when control voltage is applied from the ignition or the appropriate controller in the car. Because of the high current involved during the start-up, all elements in this high-current circuit must be carefully designed and well maintained. Insufficient quality of any single element causes additional drop in the voltage supplied to the starter motor and thus reduces power generated by the starter.

The switch contains two solid contacts and one moving contact. The moving contact is put in motion with a retractable core (so called plunger). In starters manufactured today, electromagnetic switches are frequently used in mechanical structures related to the so-called Bendix system.

How a starter electromagnetic switch works

1. Initial phase
   Ignition is switched off. The flywheel gear and the pinion are distant from one another.
2. Phase one
   Once the ignition is switched on (engine start-up), voltage is supplied to clamp 50 of the switch. The flow of electric current through both coils generates two streams which sum up and retract the plunger. The coil with the larger-diameter wire and the motor switched on in series form a low resistance circuit. This results in high current, strong magnetic flux, and high retracting force. The plunger gets retracted and the pinion is moved towards the flywheel, and contacts 30 and 45 are closed. This phase lasts less than 1 second.
3. Phase two
   Switch contacts are closed and the ignition is still switched on (in the engine start-up position). Once the switch contacts (30 and 45) close, the current in the coil with the wire of larger diameter stops since both ends of the coil have the same potential, i.e. +12V. The plunger remains retracted since the magnetic flux necessary for the plunger to remain in this position is much lower. The proper start-up of the starter motor occurs.
4. Phase three
   The switch contacts are closed – the ignition is switched off. The switch contacts (30 and 45) remain closed for a short time. Power supply to switch clamp 50 is cut off. Both coils are now connected in series and fed from the side of contact 45.  Thus connected, the coils generate fluxes of opposite directions. Since the same current flows through both coils and the number of windings is comparable, the total flux is marginal and the plunger returns to the rest position. Contacts 30 and 45 are open.

Alternator is used in vehicles and Diesel engine-powered machines. It is an electric motor which transforms mechanical energy to electric current. Alternator is intended to ensure appropriate loading of the battery and supply power to the installed devices.

1. Bearing
2. Pulley
3. Stator
4. Bearing
5. Slip ring
6. Regulator
7. End cover
8. Rectifier
9. S / R / E bracket
10. Rotor
11. D/ E bracket

Starters are regularly modernised. They satisfy basic requirements to an ever higher degree and get more and more failure-free.  Despite the typification tendency observed worldwide, there are several thousand different types of starters today.  Frequently, the only difference between individual types comes down to geometrical parameters related to the method of mounting the starter in the engine.

1. Bracket
2. Solenoid
3. Fixed contact
4. Field Coil
5. Pinion
6. Lever
7. Gear
8. Armature
9. Commutator
10. Brush Holder
11. Cover

Before you conclude that your starter is defective, eliminate any other causes which might affect its operation.  Try the following procedure.

1. When the starter does not respond to the turn of the ignition to the starting position, check whether there is any voltage on clamp 50 of the starter (thin wire) using a special instrument or indicator light.  If there is no voltage, the car electric installation may be defective.
2. If the starter moves the engine but the revolution is low, take two measurements with a voltmeter, as shown on figures below.  Both measurements should be taken when starting the engine in subsequent attempts to turn the starter on. 

Never keep the starter working for more than 5 to 10 seconds.  Repeat the attempts at intervals of several dozen seconds.

• Measurement one – measure the voltage on battery clamps when the starter is working – if the measured voltage is lower than 8 V, the battery is discharged or defective. 
• Measurement two check voltage between starter connection clamp and starter housing. The same as at first measurement, voltage should’t be less than 8V.