Engine’s starting system and its problem diagnosis
We use affiliate links and may receive a small commission on purchases. Read more about us.
To keep the engine running, the engine’s combustion system first needs to get the necessary torque to be started.
The engine’s starting system generates that torque through a starting motor to the crankshaft of the engine.
Once the combustion process starts, the whole system becomes autonomous to keep the system running.
Let’s dive deeper into the explanation-
What is a engine starter motor?
A starter motor is a mechanical device that converts the electrical energy of a battery into mechanical energy.
Through a small pinion gear attached to the end of the starter, the motor transmits that energy to the main crankshaft of the engine.
The engine’s starting system is the process of cranking the engine to initiate the combustion and electric fuel injection (EFI)process.
How does the engine’s starting system work?
The constituent parts of an engine’s starting system are-
- Ignition key
- Battery
- Starter motor
- Solenoid
- Pinion gear
- Flywheel
- Alternator
The starter motor is placed in close proximity to the Flywheel. The Flywheel is attached to the end of the crankshaft that has a certain number of teeth in its perimeter.
When the ignition key of a combustion engine is turned on, a good amount of current runs towards the starter motor.
A solenoid attached to the starter motor controls the current by creating an electromagnetic field.
The electricity that is drawn from the battery rotates the pinion gear.
The pinion gear at such a juncture gets connected to the flywheel and starts rotating the flywheel.
The rotation of the flywheel cranks the engine initiating the combustion process.
The pinion gear afterward disconnects from the flywheel, and the combustion process keeps the engine running on its own.
An alternator in the engine’s starting system however keeps the electrical system of a vehicle functional.
An alternator transforms the mechanical energy of the engine into electrical energy. At the same time, an alternator keeps recharging the battery so that the battery can produce essential energy for the starter motor to crank the engine.
Engine’s starting system’s problem diagnosis
For various reasons, the engine’s starting system may not function properly. Starter failure, pinion engagement error, solenoid failure, and no alternator output are some of the common engine starting system problems that can be solved through diagnosis.
Let’s dissect each of the problems, and how you can solve the issues-
1. The starter fails to operate
Probable reasons | Solutions |
Insufficient battery charge | Charge the battery |
High torque in the starting motor control valve | Check battery connection and cables |
Open starter switch or solenoid switch | Ensure a stable cable connection |
Broken or damaged brush or low spring tensile | Repairing or replacing the brush and spring |
Open field winding or short-circuit | Proper inspection |
Open armature winding | Repair or replacement |
2. Starter turns but pinions do not engage
Probable reasons | Solutions |
Misaligned armature shaft, pinion, and starter housing | Aligning the shaft, pinion, and starter housing |
Faulty switch | Repair or replacement |
Closed drive connection | Opening the connection or replacing the drive |
Faulty pinion | Replacement |
Weak spring tension | Replacing the spring |
Armature spins faster than the engine | Replacing the armature |
3. Solenoid failure
Possible reasons | Solutions |
Insufficient storage battery charge | Charge the battery to the right level |
Faulty ignition switch | Repairing or replacing the ignition switch |
Open control circuit | Inspecting the solenoid, relay switch, and connection |
Sticky solenoid plunger | Cleaning the solenoid plunger |
Faulty solenoid switch contact | Repairing |
Faulty field winding | Repairing the faulty field winding |
4. No-alternator output
Possible reasons | Solutions |
Faulty or damaged armature core | Inspecting the armature ball bearing and replacement if necessary |
Ineffective armature bearing | Replacing the bearing |
Decayed armature shaft bushing | Replacing the commutator ends |
Open or ground alternator stator coil | Adding new coil |
Short or open circuit on the alternator rectifier | Replacing the rectifier |
Open or grounded transistor, register, or diode short | Replacement |
5. Excessive or over-charge in battery
Possible reasons | Solutions |
Fast engines increase the voltage of the alternator which may cause the electrolytes of the battery to overflow | Stopping the engine |
Short or ground on the rotor field winding | Repair or replacement |
Faulty regulator | Repair or replacement |
The electrolyte level in the battery is low | Filling up the battery with electrolyte |
Grounding on the field coil | Repair or replacement after inspecting |
Short circuit on the field coil | Inspect through the Avometer and replace it if necessary |
6. Diode failure
Possible reasons | Solutions |
faulty voltage regulator | Inspection and replacement if necessary |
Lose or damaged alternator belt | Aligning tension or replacing the belt |
Faulty alternator | Servicing or replacing the alternator |
Burned battery terminal connection | Cut the previous connection and attach a new connection |
Faulty heat sink | Repair or replacement |
Faulty earthing in the diode or rectifier | Correcting the earthing |
Engine’s starting system
Previously, people used to start an engine by using their hands through a handle. But that was near the primitive ages.
Modern combustion engines are more advanced with an electrical starting system.
The engine demands a thrust before it can start the automatic combustion process.
The starting system produces that thrust to transform the electrical energy of the battery into mechanical energy. If you facing any problem with satarting your engine, you can use external jump satarter like nuco jump.
Advantages of the engine’s electrical starting system
- No external pressure or force is required to crank the engine
- Troubleshooting is much easier with an electrical starting system
- Power alignment is electrically controlled
- The chance of personal damage is much lower
- Most importantly, an electrical starting system keeps the parts protected from wear and damages
