Hello. I have a high pressure cleaner and the other day it startet to smeel like overheat motor so I stop. I saw too much sparks in the motor (it is a universal motor) so I changed the brushes, but the sparks are still there. This video is with the new brushes

In case you can't see the video

The conmutator seems damage by the sparks, and the motor shaft gets hot after few seconds.

The circuit is very simple, only the motor, the pressure sensor and a small capacitor. What could be the problem?

The new brushes could be longer than the old ones so maybe they apply too much pressure over the conmutator

Thank you

best regards

 

Armature is probably shorted.

 

The gaps between the rotor contacts need cleaning and testing for shorts, also check the field coils for shorts.

 

Thanks for your answers.

Ok, I´ll check the armature, and clean the contacts, but I have no idea about checking the field coils. How can I do that?

 

use an ohm meter and check for continuity and short to ground.

 

Ok, I´ll check the armature, and clean the contacts, but I have no idea about checking the field coils. How can I do that?

Usually modern armature commutators have wearable material that keeps the segments clear, a motor in good working condition does not usually need treatment to the com, until it has to be undercut in a lathe.
That one exhibits the classic shorted armature or field, most likely the former.

 

Thanks for your answers and sorry for the delay in mine.

I have checked but there is no conductance between the conmutator or brushes with the armature neither the saft of the motor. There is one of the contac of the conmutator that seems a bit loose but it maybe not the origing but the consequence got the overheating

 

All the collector motors have hard vibrations into rotor winding, thus even inspite of hard gluing with lack or epo the probability to have a short-circuit between neighbor wounds are very high. Right, exists a probabilities with less severity, too hard carbons, too mild springs of carbons, carbon-filled gaps in collector, oxidized collector surfaces etc. But 80% that rotor must be throwen out. Sad to tell.

 

Thank you. Ok I'll try to find a replacement for the motor.