How does the starter motor work and what parts does it have?

We explain everything you need to know about this component, its parts and its repair.

A little over a century ago start a car it was not as simple an operation as turning a key or pressing a button. The first combustion vehicles required turning a lever by hand that served to move the crankshaft. This little help was used to start moving connecting rods and pistons and start the combustion processsince, without this inertia, the motor could not be started.

since the year 1911this task is done by starting motor, a fairly simple component that does the same job, but in a much less tedious and automated way. Throughout the following lines we will talk about this component, its functions and also

What is the starter motor?

Behind something as simple as a button, there is a fairly complex system that allows our car to start automatically

The starter motor is a component used to start the engine of a combustion vehicle. It is located near the gearbox, and its function is none other than to convert electrical energy from the car battery into kinetic energy to turn the crankshaft.

When a starter motor does its job correctly, the different parts of the engine such as the pistons, the connecting rods or the camshaft begin to perform their tasks. combustion cycles. Without this help, the engine would not move, since, although it seems a contradiction, the propellant must be in motion to be able to generate kinetic energy.

How does a starter motor work?

This component does not have a much more complex operation than that of any electric motor that you can find in an appliance. Once we turn the ignition key of the vehicle, the starter motor will receive battery electric power. The starter has a rotor with a magnet and a stator with copper windings. Electrical energy powers the coils, creating a magnetic field that turns the rotor. This movement is transferred to the crankshaft, carrying out the process that we have explained in the previous paragraph.

The starter motor ends its task once combustion has started. In the case of gasoline engines, this occurs when the spark plugs create the spark that ignites the fuel. As soon as the starter motor finishes its function, the alternator of the car starts generate electricity to power the vehicle and keep the battery charged for later use.

starter motor parts

Although it does not usually fail, any problem in one of the components of this part can cause our vehicle not to start

The starter motor of a car is made up of several parts that work together to start the vehicle’s engine. They are the following:

• Rotor: is the component that rotates. Its movement is transferred to the crankshaft of the vehicle. It is composed of a drum, a winding and the collector.
• stator: It is a fixed component that is inside the starter motor and provides the necessary electromagnetic field to turn the rotor.
• solenoid or contactor: is an electronic component that controls the electrical current that goes to the rotor and stator.
• Drive or drive pinion: is responsible for transmitting the force of the turn.
• Case: It is usually made of iron. It is fixed to the gearbox and houses the rest of the components inside.
• inductor coil: is a wire that is part of the electrical circuit that is connected to the casing.
• brushes: are made of carbon paste and graphite. Its mission is to emit electrical energy towards the rotor.

Any failure in one of these components It can cause the assembly to stop working, thus preventing a combustion vehicle from being able to start.

Symptoms of a faulty starter motor

starter motor it is not usually a component that tends to fail often. Throughout the useful life of a car, at most it will break once, as long as we have a car with many years behind it.

If when you connect the key or press the button, your engine does not make any kind of movement, the most normal thing is that what is failing is the starter motor. In other cases, when the starter is damaged, it can turn very slowly, or even make sounds. In some cases, we will hear ‘click’ repeatedly, but the component will not have enough power to start the vehicle.

Sometimes the starter will give a little warning. You will notice it because it will cost you more and more to start the vehicle. In these cases, it is often interesting visit the workshop before it fails completelysince we can save the money of having to hire a crane.

Broken starter or dead battery?

The battery and the starter usually have very similar symptoms when they fail

With a dead battery you will not be able to start your car. And with a broken starter – neither. Most of the times that we find ourselves before a car that does not start is due to the battery. However, there are several symptoms that can help you determine if your car won’t start due to a dead battery or faulty starter. The most significant are the following:

• The starter motor is what we hear when we turn the key, just before the engine explodes. If you perceive that spins slowly or makes a strange noise when turning, it can be both. Typically the battery is weak, but still has enough charge to crank the starter. However, we could not put our hand in the fire and ensure that the starter is not faulty.
• If when you turn the key, the starter does not sound, it is normal that it is the battery that is failing. You can make sure it’s the battery by taking a look at the instrument cluster. It does not turn on? It’s the battery.
• If the instrument cluster lights up, but the starter movement is weak, check the box in case a pilot lights up. Normally, a starter motor failure is usually represented by the engine fault warning light.
• Lastly, if he starter turns, but the car engine does not start, the problem is probably the starter motor. The fact that the engine turns means that the correct energy from the battery is reaching it, so in these two cases, it will be the starter motor that has problems doing its job.

Can I start my car without a starter motor?

You can tow a vehicle to start it as long as it has a manual gearbox

If you have paid attention during the beginning of the article, it is possible that you already intuit what the answer is. Indeed, if we find ourselves in a hurry, we can start the car even if the starter motor is bad. However, we anticipate that there are many cars in which it is not possible to do this trick that we are going to explain to you.

Just like when we find ourselves without a battery, it will play push the car to start it. Basically, we will give the crankshaft the necessary movement to start the engine. It is necessary that the transmission It is connected – that is, that there is a gear engaged, otherwise the rotation of the wheels would never reach the engine. As a general rule, this trick will only work for us in cars with manual gearbox. In addition, it is much more complicated to make it work on a diesel than on a gasoline, since diesel vehicles have more trouble starting when cold.

To do the process, you need the help from another person. In a wide space, and that does not pose a risk to other people, we will put ourselves in the driver’s position and we will put the second gear. We will leave our foot on the clutch and we’ll drop all the rest. Immediately afterwards, we will need them to push the vehicle until they reach a speed of about 10 to 15 kilometers per hour. When the vehicle is already at the correct speed, we will release the clutch abruptly and the engine will start as long as the vehicle’s battery is in good condition.

How much does it cost to repair a starter motor?

The starter is a cheap component, but replacement will depend on the price of labor

Each car is a world, so repair this component It may vary depending on the range of the vehicle itself or the scarcity of the component for our unit in question.

If we take a look at the typical car spare parts websites, the part can cost us a few 80 euros. In the event that you dare to do the repair yourself, it will only cost you that.

On the other hand, if you prefer to have the operation done in a workshop, the price of the component must be added workforcehence It will cost you between 200 and 500 euros.