BOSCH STARTER 0001116003 12V 0.9KW 9T

TIPS
An Auto Starter Motor is an electric motor that turns over or "cranks" the engine to start it. It consists of a powerful DC (Direct Current) electric motor and the auto Starter Motor Solenoid that is attached to the motor (see the picture). In most cars, an auto Starter Motor is attached to the transmission
The AUTO STARTER motor is powered by the car battery. To turn over the engine the Auto Starter motor requires a very high electric current, which means the battery has to have sufficient power. If the battery is discharged, the lights in a car might come on, but it won't be enough power (current) to turn over the starter motor.
What are the symptoms of a bad auto starter motor: With the fully charged battery, when starting a car, nothing happens or there is a single click, but the auto starter motor doesn't run, even though there is a 12-Volt power at the auto starter control terminal.
Another symptom is when the auto starter motor runs, but fails to turn over the engine. Often, this might cause a loud screeching noise when starting the car. Of course, this could also be caused by damaged teeth on the ring gear of the flex plate or flywheel.

How Does an Auto Starter Motor Work?
When you turn the key in your car’s ignition, the engine turns over and then cranks. However, getting it to crank is actually much more involved than you might think. It requires a flow of air into the engine, which can only be achieved by creating suction (the engine does this when it turns over). If your engine isn’t turning, there’s no air. No air means that fuel can’t combust. The starter motor is responsible for turning the engine over during ignition and allowing everything else to happen.
How your Auto starter motor works?
Your auto starter motor is really an electric motor. It engages when you turn the ignition to “run” and turns the engine over allowing it to suck in air. On the engine, a flexplate or flywheel, with a ring gear around the edge, is attached to the end of the crankshaft. On the auto starter motor, there’s a gear designed to fit into the grooves of the ring gear (the auto starter motor gear is called a pinion gear).

When you turn the ignition switch, the auto starter motor is energized, and the electromagnet inside the body engages. This pushes out a rod to which the pinion gear is attached. The gear meets the flywheel, and the auto starter motor turns. This spins the engine over, sucking in air (as well as fuel). At the same time, electricity is sent through the spark plug wires to the plugs, igniting the fuel in the combustion chamber.

As the engine turns over, the auto starter disengages, and the electromagnet stops. The rod retracts into the starter once more, taking the pinion gear out of contact with the flywheel and preventing damage. If the pinion gear remained in contact with the flywheel, it’s possible that the engine would spin the auto starter too fast, causing damage to it.