received new used 646se with a pair of batteries inside

[Burgerman]

A totally destroyed brush, and a new (almost) brush...

Which do yours look like?
These ruined/destroyed ones like on the left, came from my 2 year old chair.
When I hit it with the compressed air and spun the motor a huge cloud of black dust came out.
The oe on the right was its replacement, new. After a month.

Not all brushes look the same. Some are shorter even when new. The only way to actually KNOW is to compare your old ones to the MANUFACTURERS brand new ones for that motor specifically. By then you already have them! So fit anyway.

[yeshelp]

HI
ok I have been able to remove the stuck brush with a bit more insistance and back and forth movement. It was compressed powder around the brush that was creating a layer of material creating a blockage.

I plan to brush the holes and brushes with a End-Tuft Soft Tapered Trim Toothbrush parondontal toothbrush. Ai says that The bristles (filaments) themselves are made of a synthetic material like nylon or polybutylene terephthalate so that seem ok.


To look at the Armature, you write Yes turn the motor. Look with a light/torch. Look at all of it to make sure no damage.
When unpluged and on freewheel the axle does not want to turn nor the armature i tried to push a bit with a screwdriver. Probably since the brakes are automatically on when unpluged. So I guess your suggestions is to leave the 4 holes open and plug the motor back in the power module to look by he hole window? That armature probably turns fast when the joystick is pushed. I might only be able to look at random spots instead of checking all the armature if it turns too fast but I can try to see what I can see.

About the black dust. Opening the can would be better but the pozi 1 2 3 dont really fit deep in the front cap screws of the motor. There is probably rust layer preventing to go deep in the bottom. It feels like i would strip them if I try them like that. Also the motor probably has a seal or glue (maybe dried) that would probably not be as water proof after if I open it. The motor works so Im not sure it is a good idea to open it .

What i understand from your suggestion is to just leave the 4 holes open and blow air east west north south a coulple of times while the motor is plugged in and moving from the joystick .Is that what you meant or did you mean to blow air in the holes unpluged while turning the motor in my hands manually like literally turning the motor on itself ?

Idont know if the black powder would be air pushed on other parts inside the motor instead of coming out from the holes ... Could it bring new problems or is it still a better choice than doing nothing about it ?

When you say take a while, just to have an idea, would it be blowing air for 2 min 5 min 10 minutes ? Since the motor will be pluged in but in my hands should I try to position the holes lower(motor vertically ) so that at least gravity brings the powder in this part? I dont know if there are separations in the motor but if it kind of open space blowing while the motor is vertical (hole at the bottom)could make sense.

thanks
here are pict of the front screws