2 year old MA. Should I replace the motors?

[stberlin]

...almost 2 years old. There's a fluctuating noise coming from one of the motors (can't pinpoint which one). It sounds like the cooling fan but it's not.
Has anyone replace all four motors? How long do these drones last?

 

[bumper]

There are two small sealed bearings in the motor. Typical bearing life for intermittent duty starts at a minimum of 8,000 hours or so, but this is predicated on environment. It's more likely that there's debris in the motor than a bearing failure, but it's also not unheard of to have bearings fail early.

Turn each motor by hand to feel it. There should be pulses caused by the magnets but no grinding or other than smoothness between those pulses. You can also listen to the motor using a screwdriver. Props off, and running at idle, put the handle of the screwdriver to your ear and rest the end of the screwdriver on the arm below the motor attach. The motors won't be free of noise, of course, but it should be fairly smooth, consistent, and one motor shouldn't be a lot louder than the others.

On the M2, and probably on the MA as well, the motor and arm are sold as an assembly. I've replace both front and back arms on my M2, after slipping with it on icy steps, hidden damage (well, I didn't see it anyway) and subsequent free fall crash. The chore involves disassembly of the drone and soldering a bunch of wires. There's also an antenna wire in each front arm, but those plug into the board.

 

[monty.roman]

if you connect your MA to DJI Assistant software on PC, you can test ESCs or even spin individual motors and determine the faulty one.

 

[WithTheBirds]

There are two small sealed bearings in the motor. Typical bearing life for intermittent duty starts at a minimum of 8,000 hours or so, but this is predicated on environment. It's more likely that there's debris in the motor than a bearing failure, but it's also not unheard of to have bearings fail early.

Turn each motor by hand to feel it. There should be pulses caused by the magnets but no grinding or other than smoothness between those pulses. You can also listen to the motor using a screwdriver. Props off, and running at idle, put the handle of the screwdriver to your ear and rest the end of the screwdriver on the arm below the motor attach. The motors won't be free of noise, of course, but it should be fairly smooth, consistent, and one motor shouldn't be a lot louder than the others.

On the M2, and probably on the MA as well, the motor and arm are sold as an assembly. I've replace both front and back arms on my M2, after slipping with it on icy steps, hidden damage (well, I didn't see it anyway) and subsequent free fall crash. The chore involves disassembly of the drone and soldering a bunch of wires. There's also an antenna wire in each front arm, but those plug into the board.

The bearings are shielded- not sealed. Sealed bearings in these small motors would rob us of valuable flight time to a not insignificant extent. The obvious disadvantage is that the lubricant can more easily leave the race in service leading to increased wear and noisy operation. Your estimations as to service life may have applicability to good quality bearings- who knows what we end up with in there motors. A failure in service should not be an unexpected eventuality.

 

[old man mavic]

there is no set life span for the motors it's all down to use and the conditions where you fly and of course if you crash ,when you do your airframe checks just make sure they don't have any debri in them, an air puffer is handy for removing sand and dust, if you are in any doubt about any of the motors you should replace them,as a failure in flight could have serious consequences if it falls from the sky you need to weigh up the risks against the cost of fixing the issue and then decide whether to repair or replace

 

[bumper]

The bearings are shielded- not sealed. Sealed bearings in these small motors would rob us of valuable flight time to a not insignificant extent. The obvious disadvantage is that the lubricant can more easily leave the race in service leading to increased wear and noisy operation. Your estimations as to service life may have applicability to good quality bearings- who knows what we end up with in there motors. A failure in service should not be an unexpected eventuality.

You are correct, shielded is what I meant to say, (that's how that goes when you are days away from 75 and only a limited number of active brain cells remaining - smile).