GY 601 - S9251 Servo feels gritty when rotated.

[david.read]

DavidH,

Thanks for the advice on the GY601 the other day. I have done what you recommended and found it to help.

I have always found the tail to flicker during a climb out, but i guess this is engine related.

As per Subject: I removed the servo support bracket on my Fury to expose the servo wheel, i was planning to lessen the distance from 19.5mm to between 16-18mm as you recommended, during this i noticed a gritty feeling to the servo. I have removed the cover and inspected the gears. - They look and feel fine.

I think the grittyness must be in the motor or bearings or something! Saying that the roughness is only at one point.

Has anyone out there had a problem like i have explained?

Hope to hear something.

David Read

[DavidH]

David,
There is the possibility that the motor in the 9251 is going bad. I suggest sending the servo to the service center you use and let them check it out.
From my experience the 9251 will turn very smoothly by hand when there is no power on it.
So if it is rough turning and it is not in the gears or bearings. It possibly could be in the motor. You might trying turning the motor only by taking all the gears out of the servo. You should be able to use a finger nail to turn the motor only.

David

[david.read]

Thanks DavidH,

I guessed maybe as much. Not sure what it quite implys, but i will ground the Fury and send the servo away anyway to get it checked over.

Thanks for the speedy reply. :D :D :D

Regards,

David Read

[steve kra]

mine was like that after a crash therefor i replaced it. i thought i read somewere if the motor windings start seperating they will begin rubbing the magnet or internals of the motor. and this was on the 9251

[3DME]

I bought a brand new 9251 and it was "gritty" in spots. That is a good explanation for the sound/feel it has. So I noticed this when I was installing the servo. I stopped the installation and took it back to the hobby shop to get a new one. We opened 4 or 5 9251 servos and all of them were "gritty" in spots. So i kept the original that I bought and have been flying it ever since. So far no problems. I would like to see what Hobby Services says about the "gritty" feel, so if you send it back please post the results.


Mike

[david.read]

Gent's - Thanks for your input.

My friend also has a GY 601 and his servo feels perfect! Thats partly the reason i think mine isn't. I have JR 8301's on my CCPM and when i swish them they move freeley, without any feeling of resistance or grittiness.

I will post up and let you know.

PS# I guess there is always a chance that Ripmax UK already know it's coming, if they have the internet, and look at this site. :)

Thanks Mike

Talk soon. :)

[david.read]

I called Futaba UK today, and spoke to a service tecknision. He explaned that a high speed servo will feel gritty when rotated, it's just a characteristic of the faster gearing and metal components...

He thought that if the motor was under load due to a loose wrap of copper, or something, then at some point the motor would fail completley.

I stripped mine again and used an old tooth brush to fully clean the gears, this proved to be sucessful as, the servo only feels gritty now, and not lumpy in spots as well.

He said a 9251 can be traded in for the new 9256 for £70 Sterling.

I will stick with what i have for now.

David

[jetBlue]

I felt the same thing on mine this past year before IRCHA. I bought a spare, went to IRCHA, and sent the other in for repair. It came back with a clean bill of health. Apparantly, this is OK. The new one I got felt the same too. "It's a different sort of gritty feel than that of a servo that's wearing out" is what the tech said after I called and asked about it. I have 4 9251's now and they all feel the same. No worries.

Hope this helps.

[david.read]

Thanks Dave,

Piece of mind restored.

Regards,

David Read