About starter motor brushes:

The starter motor is a crucial component of your car’s electrical system, responsible for turning over the engine when you start the car. One of the key components of the starter motor is the starter motor brushes, which transfer electricity from the battery to the starter motor itself.

Starter motor brushes have spring pressure to push against the starter motor commutator inside the starter motor. There is a series of brushes used to connect the electrical current from a static conductor to a dynamic conductor. The brushes make contact with the commutator and as the starter begins to rotate the brushes reverse the flow of current to the armature alternatively. Starter brushes carry the full flow of current through the motor.

In a starter motor, there are usually about 4 or more brushes with two as a positive brush and the other two as negative brushes. The material of this brush is usually made of copper and carbon, to keep the brushes and commutator from wearing out. 

Over time, starter motor brushes can wear out and may need to be replaced. If you’re experiencing problems starting your car, it’s possible that the starter motor brushes are the culprit. Other signs of a problem with the starter motor brushes include a clicking noise when starting the car, or the starter motor not engaging at all.


Causes of brushes to wear in starter motors:

In the case of starter motor brush faults, sparks can occur between the starter motor and commutator and the brushes due to unsmooth contact of the brushes.
  • Brushes experiencing damage due to electrical underloading or overloading
  • Starter Motor winding faults
  • Voltage surges to the motor
  • Issues with the commutator – excessive sparking / arcing caused by the worn starter motor brushes

Symptoms of a bad starter motorstarter

Common bad starter motor signs include

There are a few common symptoms of damaged starter motor brushes that you may notice:

  1. Difficulty starting the car: If you’re having trouble turning over the engine when you start the car, it’s possible that the starter motor brushes are the issue.
  2. Clicking noise when starting the car: If you hear a clicking noise when attempting to start the car, it could be a sign that the starter motor brushes are worn out and not making good contact with the starter motor.
  3. Starter motor not engaging: If the starter motor is not engaging at all, it could be a sign that the brushes are completely worn out and need to be replaced.
  4. Grinding noise when starting the car: If you hear a grinding noise when starting the car, it could be a sign of a problem with the starter motor or the starter motor brushes.
  5. Lights dimming when the car starts: You may notice the lights temporarily loose power when you turn the keys in your car. This is a common sign of a starter motor or brushes that is on its way out.

If you’re experiencing any of these symptoms, it’s a good idea to have your starter motor inspected as soon as possible. Ignoring the problem could lead to more significant issues down the road


Starter motor servicing and replacement in Hamilton

If your car starter motor is not working correctly and needs a replacement, we are here to help you, to replace it according to your car’s needs.

At Grimmer Motors, our team of experienced mechanics provides solutions to a variety of starter motor-related issues and other electrical-related issues. Please contact us by clicking on the button below.

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