Hi guys,
Today I thought I'd open up my motor (HobbyKing X-Car 6.5T) because I thought it sounded a bit grainy... and I found it was literally full of sand!
I've driven a lot on (loose) sand this winter in a horse riding school. The motor has a closed case so it seems all of it entered at the point where the wires enter the can.
I can't get all the dirt out without compressed air, but most of it is gone now: it's not in there anymore like standing water

and I'm pleased to see the dirt didn't leave any corrosion. I also noticed the magnet/rotor has some scratches on it's anti-rust coating - but other than that the rotor seems solid.
It's the first time I'm doing maintainance on a motor, so I'm wondering if I opened it right on time and I can get away with a quick cleanout (toothbrush), or if it's recommended to do more work to it (and if so, what)?