Possible motor problem

[Only1nexus]

Ok, After about a month of not being able to fly( weather, high winds) I was able to go out today. 6mph winds 8 mph gust. As i was taking off and letting it hover for a few seconds I noticed a slight hum in one of the motors. I landed it shut it down and reinspected every thing took the blades off and put them back on and made sure all was tight. I lift off again, and i still hear it. Now I am thinking maybe it was because of some of the wind I have maybe it was the blades and or drone fighting the wind on the quick gusts. Well when I was bringing it in for landing I let it hover about six and a half feet up and I noticed the landing gear was vibrating and so was the body of the Q500. I hooked it up to my computer and did the motor test and it all checked out. Is this normal or should I be contacting Yuneec?

 

[NorWiscPilot]

Ok, After about a month of not being able to fly( weather, high winds) I was able to go out today. 6mph winds 8 mph gust. As i was taking off and letting it hover for a few seconds I noticed a slight hum in one of the motors. I landed it shut it down and reinspected every thing took the blades off and put them back on and made sure all was tight. I lift off again, and i still hear it. Now I am thinking maybe it was because of some of the wind I have maybe it was the blades and or drone fighting the wind on the quick gusts. Well when I was bringing it in for landing I let it hover about six and a half feet up and I noticed the landing gear was vibrating and so was the body of the Q500. I hooked it up to my computer and did the motor test and it all checked out. Is this normal or should I be contacting Yuneec?

Only 1...

When you did the motor test, assuming you had the props off, did you notice a vibration with any of the motors?

With a vibration as you describe, my first candidate would be an out of balance prop. If you have a couple spares, swap two at a time to see if you can eliminate the vibration. If the vibration goes away, one of the two removed props is likely the culprit. From there you should be able to narrow down to the one.

Possible to have a bad motor, but... try the simple first if a motor cannot be isolated.

Jeff

 

[Steve Carr]

Blades on the Q500 are easy to balance and it's not unusual for them to need it. Since the Q has 13" blades a small out of balance condition can produce a lot of vibration. Here is a link for the rod.
Speedy™ Prop Balance Rods
I just set it on top of a water glass on a level surface and it works well. You can use a piece of scotch tape on the underside of the prop to weight the light side.

As far as motors......rotate each by hand to see if they feel smooth. Check side play and end play. They should all feel about the same.

 

[Only1nexus]

Only 1...

When you did the motor test, assuming you had the props off, did you notice a vibration with any of the motors?



Jeff

No I did not notice a vibration when testing and yes the blades were off, but the back left motor seemed to have a different sound. Not sure how to explain the sound, I will try and get a video and sound clip put up when I can.

 

[Steve Carr]

No I did not notice a vibration when testing and yes the blades were off, but the back left motor seemed to have a different sound. Not sure how to explain the sound, I will try and get a video and sound clip put up when I can.

It always seems like a least one motor will sound different but that doesn't mean it's a bad motor. Props are always the main source of vibration.