Broken brush set by excessive amount of dirt

Replacing the drive axle rubber boot was a quite labor intesive task. I had not done it previously to any car so there were many new things to learn on the way. After a few late evenings both outer and inner rubber boots were replaced and Corolla was ready to hit the dirty winter streets again!

One day while driving my usual trip to work I suddenly noticed a clear lack of power. I was just getting on top of an uphill about 1km away from my workplace and tried to figure out what could have caused the power loss. As soon as I turned down the volume from the car's stereos I heard some loud whining. Luckily I was just beside a parking area where I rolled the car and walked to work. While rolling the car without the motor spinning the whining noise disappeared so it was pretty obvious that the motor was damaged.

After the workday the Corolla was towed to its garage to get repaired. All electrics were working nicely so I could concentrate on finding the problem from the motor.

 After removing the brush set cover it was easy to confirm that the motor was hurt. The commutator looked very bad and the smell of burned brushes was strong.

 Inspecting the removed brush set made it clear that the brush set was destroyed and it would not be able to be repaired. Brush springs had been cracked, conductors had detached from brushes and some brushes had been welded on their housings.

I crawled back under the car to see if the rest of the ME1003 motor could be rescued. Cleaning the motor and sanding the commutator strengthened my conclusion that this failure was probably due to excessive amount of dirt on the commutator and brushes. Possibly a small stone was the final cause of the sudden breakdown since the commutator had a deep groove that did not look to have been originated from any of the brushes.

My repairing plan is to purchase a new brush set and to sand the commutator back to its original shine. Also not to let this happen again I will build some air filtering on the back of the ME1003 motor.

While waiting for the spare parts to be imported I've been driving our gasoline Mondeo again. I miss driving the Corolla, hope to get it back on the road soon :)