700N DFC Clackety clackety in flight?

[Delarado]

Guys, been flying my 700N DFC today and over the course of the day have been having a worsening clackety clackety sound while flying.

I have holographic stickers on my blades, the corner of which had lifted on one of them, so I thought it was that - However, I cut off the loose corner, and the sound continued.

I took the head and main gear out at the field, the shaft bearings are pretty good. Not perfect, but not bad by any means. There is maybe one or two tiny notches in both of them, but I dont think they are causing the problem.

I was thinking maybe rear bearing, so I started the engine without the head attached and it sounded perfect.

I rotated the tail with the head off and could hear some clicking that sounded like it was coming from the front gearbox, so I took that out expecting to find a collapsed bearing, but they are all perfect!

Has anyone else had this issue? Its difficult to describe the sound, but as mentioned, my first thought was that it was half a holographic sticker on the blades hanging off...

[markb75]

if your turning the head with the tail attached it might be the bearings in the torque tube.just a thought
as i no longer have a 700n dfc

[tonystevens]

is your front torque tube bevel gear mesh tight?, front bevel gear needs to be pushed back in as far as it will go or you will get that type of sound

[Delarado]

I think so...Its been flown quite a few times, maybe its worked its way out... Ive got it all apart and can't see whats wrong, maybe it'll be one of those times you put it back togehter and its fine again

WIll I hear it with no load on the engine if its the rear bearing?

[flatspins]

Are you missing any teeth from the main gear?

[tonystevens]

rear bearing noise is pretty obvious sound to me, almost sounds as if there's no lubrication in the engine at idle, not so obvious once its spooled up.
clutch hasn't snapped has it?

[panosg]

Like Tony said, sounds like clutch noise.
I had the same noise on my 600n and the one end of the clutch was broken off!

Worth a look mate!

[Delarado]

engines out, clutch looks fine, everything looks fine!

The bearing in the centre of the clutch bell is a little notchy, but as far as i can tell, all it runs is the start shaft.

EVerything else seems fine!!!

[dieselcarb]

Any teeth missing on the umbrella gear thats vertical ? Or auto gear to the same part but the straight cut gear? Thats all I can think of. My 600 made clackaty noise after a big bird attacted my tail destroying umberellas and and auto chaffed the tips off auto to tail gears also making that nasy noise. Good luck and hope u find it soon
All the best terry

[malloryn]

engines out, clutch looks fine, everything looks fine!

The bearing in the centre of the clutch bell is a little notchy, but as far as i can tell, all it runs is the start shaft.

EVerything else seems fine!!!

Check the thickness of the liner. Mine was too thin right out of the box.
The clackety clack sound could be the clutch slipping. I can't remember but I think mine made a similar noise.

[jwatts007]

locktite the bearings (new ones) too the pinion then a little CA too fix them in the clutch housing...works a treat and makes it all run smooth....

[Delarado]

It turned out in the end to be my hologram stickers lifting on my blades; I only checked the leading edge, it turned out to be a little corner on the trailing edge that I Didnt check, the nitro had got under it and started it lifting by 2mm or so on the whole tail edge!

[SaneAdam]

It turned out in the end to be my hologram stickers lifting on my blades; I only checked the leading edge, it turned out to be a little corner on the trailing edge that I Didnt check, the nitro had got under it and started it lifting by 2mm or so on the whole tail edge!

Have had that before. Once forgot to take the protective clear sticker off a new set of blades.... 30 seconds into the flight there was a huge bang..... landed quickly only to find the sticker had come off and was floating back down when i landed lol

I could not believe the sound that it made....! It sounded like an explosion

[dieselcarb]

lol its funny what a noise it can create a fried balanced some blades with celotape the wrong way it made a noise clackety noise never would of thought the trailing edge would lift

[dannyboy123]

Any teeth missing on the umbrella gear thats vertical ? Or auto gear to the same part but the straight cut gear? Thats all I can think of. My 600 made clackaty noise after a big bird attacted my tail destroying umberellas and and auto chaffed the tips off auto to tail gears also making that nasy noise. Good luck and hope u find it soon
All the best terry

As Terry says I had a noise like this and it was umberella gear teeth missing