Bad motor diagnosis ?

[Andre Castro]

Dear pilot friends,

Recently my P3S has suffered an accident.
One of the propellers slightly hit a tree branch and made the drone drop like a rock into a swimming pool undernearth it.

As quick as I could, I pulled it out from the pool, removed the battery right away and was able to get rid of lots of water from it.

As soon as I got home, I left it locked in a plastic box with a couple of pounds of raw rice along with two boxes of an anti-moisturizing produtc (made for clothing). After around 1 and 1/2 months, I disassembled it and removed all rice inside.

Surpresingly enough, batteries looked good as well as the drone itself. Absolutely no warnings on the screen, for motors, ESC or whatsoever.

However, just one of the motors seemed to be working fine, other 2 (both diametrically opposed) kind of sluggish and the remaining one (diametrically opposed to the working one), was completely still.

I wonder if anyone has any suggestions of what might be wrong with it, or tips on how I can diagnose the problem.

Below, there is a video I recorded when powering the motors on.

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Any help will be much appreciated.

Cheers

Andre

 

[Andre Castro]

Also, the working motor was the most free one to spin with my bare hands.
The others seem not to be as good.

 

[N017RW]

The motors are very robust as the only moving or wearing parts are the bearings.
They will even operate underwater.

It would seem the most vulnerable parts to water damage are electronics and mostly from corrosion.

On way to test is to swap motor positions. This way you can see if it is the motor or ESC.

However all the ESCs are on the main PCB board so you're likely looking at having to replace the PCB.

 

[Andre Castro]

Thanks N017RW

That was my concern, it will be much more complicated to have the main board replaced at this time.

Wouldn´t it mean that I´d have any kind of alert anyway? You may see the LEDs are flashing green despite the problem, there is no ESC error in the DJI app... Have you seen anything similar?

Cheers

Andre

 

[N017RW]

Sorry, nothing similar experienced. Never doused a Phantom.

Pool water is often full of bad stuff... chlorine, Muriatic acid, etc.
Common Pool Chemicals

Just a divide/conquer method to troublesshoot motor vs ESC is all I can offer.

 

[Alex Baxter]

Dear pilot friends,

Recently my P3S has suffered an accident.
One of the propellers slightly hit a tree branch and made the drone drop like a rock into a swimming pool undernearth it.

As quick as I could, I pulled it out from the pool, removed the battery right away and was able to get rid of lots of water from it.

As soon as I got home, I left it locked in a plastic box with a couple of pounds of raw rice along with two boxes of an anti-moisturizing produtc (made for clothing). After around 1 and 1/2 months, I disassembled it and removed all rice inside.

Surpresingly enough, batteries looked good as well as the drone itself. Absolutely no warnings on the screen, for motors, ESC or whatsoever.

However, just one of the motors seemed to be working fine, other 2 (both diametrically opposed) kind of sluggish and the remaining one (diametrically opposed to the working one), was completely still.

I wonder if anyone has any suggestions of what might be wrong with it, or tips on how I can diagnose the problem.

Below, there is a video I recorded when powering the motors on.

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For more detailed information, see our cookies page.

Accept third party cookies

Any help will be much appreciated.

Cheers

Andre

I would imagine that the motor bearings have corroded, I'd guess they are sealed bearings, which are sealed to stop the grease coming out, but would allow water in, and would corrode the bearings. Try swapping motors, but in any case I reckon you'll have to change them all..

Good luck..

Sent from my Nexus 9 using PhantomPilots mobile app

 

[Erised]

Since you have the bird open I would change all 4 motors because they are not expensive and you get some peace of mind.

 

[Andre Castro]

Thanks guys

Will try all out and let you know the results.

Cheers

Andre

 

[Alex Baxter]

Thanks guys

Will try all out and let you know the results.

Cheers

Andre

Good luck