• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

Brushless motor repair.

Cooley

Father/Son Team
#1
Hullo, i have a situation i think you can help with.

Im on my first plane, an FT flyer. As expected i have introduced it into the ground a handful of times. (Held up reasonably well, and for two dollars i can fabricate a replacement fuselage) but what im having problems with is my brushless electric motor.

It held the first few crashes fine, even when my prop didnt. However, after this latest crash it has stopped working. There is no esc error code, when i throttle up it tries to turn but ends up just twitching. And if i turn the motor by hand it feels very snug rather than almost free spinning like before. Disassembly and cleaning did not help. Intuition tells me i bent a prop shaft or bell housing and made my motor less-than-brushless. But im hoping it will be something that wont require spare parts.

On that note would it be a pain to find a replacement propshaft for an emax cf2805?
 

earthsciteach

Moderator
Moderator
#2
You likely have either a broken motor winding or a loose solder connection on one of your motor leads. Brushless motors twitch when they are only getting 2 of the 3 phases from the esc.

Start with resoldering your bullet connectors on the motor and maybe the esc. This is the easy fix. If that doesn't work, you have a broken winding. You CAN rewind your motors, but I've had limited success with that. All of mine have burned out rather quickly after rewinding.
 

Cooley

Father/Son Team
#3
So i fixed it right after posting. Solution was a more thorough dissassembly and bathing the ball bearings in parts cleaner (jet fuel and penetrating oil) to get the grime and dirt out.
 

Cooley

Father/Son Team
#5
Unfortunately two more crashes and that ball bearing gave up the ghost. I think I reinstalled it backwards because after the next hard crash it started spilling it's guts.
 
#6
Hi,
I have problem. I have purchased HobbyKing HK6S 2.4Ghz FHSS 6Ch Tx & Rx (Mode 2),Turnigy TG9e 9g / 1.5kg / 0.10sec Eco Micro Servo (USA Warehouse,Turnigy 500mAh 2S 20C Lipo Pack,Hobbyking SS Series 18-20A ESC,Turnigy Park300 Brushless Outrunner 1380kv to build FT Swappable. But when I connect everything and start running the motor it works properly. Unfortunatly when I get, on transmitter in middle, with the control stick, the motor shuts down and I have to go down with the controling stick down and then I can run the motor again. But this is happening every time I reach the the middle on the transmitter. Can you say what could be possibly wrong?
Thanks.
 
#7
Hi,
I have problem. I have purchased HobbyKing HK6S 2.4Ghz FHSS 6Ch Tx & Rx (Mode 2),Turnigy TG9e 9g / 1.5kg / 0.10sec Eco Micro Servo (USA Warehouse,Turnigy 500mAh 2S 20C Lipo Pack,Hobbyking SS Series 18-20A ESC,Turnigy Park300 Brushless Outrunner 1380kv to build FT Swappable. But when I connect everything and start running the motor it works properly. Unfortunatly when I get, on transmitter in middle, with the control stick, the motor shuts down and I have to go down with the controling stick down and then I can run the motor again. But this is happening every time I reach the the middle on the transmitter. Can you say what could be possibly wrong?
Thanks.
Read up on the speed control you may have to learn the throttle.. push the throttle all the way up on your transmitter. Then plug the battery in.. you will hear 2 beeps.. push the throttle all the way down.. you should hear one beep.. unplug the battery.. plug it back in, test it out...

Of course the transmitter needs to be on..while you do these steps.