Motor making crunching sound?

[RCNoob]

Hello,

This AMP is only a week or two old - 9 year old as been having a wale of a time - but he's really concerned about the the sound it has started to make.

I took it apart, and one of the smaller plastic gears was a but mushed up a bit, but despite taking everything off it still sounded the same.

Is this a normal sound? I'm sure it wasn't there when we first started? It sound to be like there's a rock in there, but it's totally sealed?

Thank you

 

[Lephturn]

It is a brushed motor and it is not sealed. Not even close. You need to take those two Phillips screws out and remove the motor and then clean it out with some Electronic contact cleaner. You should be blowing it out with compressed air after each run at minimum but you definitely want to clean it properly. Like this:

I don’t recommend holding the motor by the wires, but otherwise solid guide there.

 

[Lephturn]

Also - sounds like you need a new pinion gear. The mean time between “a bit mushed up” and Completely stripped is about 3 runs. Replace the spur gear set Your gear mesh properly and back the slipper clutch off a turn.

 

[RCNoob]

thank you yet again!!

What makes you think we need a new pinion gear? I’d say in driving terms it’s only 4 hours old.

Once all the gears are back in it does sound a lot worse, so I’ll follow that video in cleaning it out.

I’ve replaced the small plastic gear that was mushy on the other side of the pinion gear.

 

[RCNoob]

Oh dear, the sound has got much worse now!

 

[Spanky]

did you oil the bushings after you cleaned it out? add a couple of drops on either end of the motor, brushed motors like that do make a bit of noise

 

[RCNoob]

did you oil the bushings after you cleaned it out? add a couple of drops on either end of the motor, brushed motors like that do make a bit of noise

thank you completely fixed!

 

[Lephturn]

Interesting. I wonder if it was spinning the bushing?

A good clean and oil does the trick!

 

[Spanky]

right on