Vibrations

[Racer38]

I picked up a second Fury at Mac's a few weeks ago and have been having a terrible time getting it worked out.

The Heli had been crashed about 2 weeks before I got it, I assumed everything was replaced but I guess it wasnt much of a crash.

Now I have replaced the main shaft which had a very slight bend in it and also the spindle. The Vibration got a little better but the gear still shakes quite a bit.
I realigned the engine to make sure that was Ok and I had just replaced the clutch pack as the other clutch liner was pretty worn and it has a different start adapter stuck on the shaft that I still cant get off.

Test Hover, still shaking, I did a couple of full throtle stick bumps and all of a sudden the thing was smooth as glass ????? I shut it down and refueld it, still real smooth till I did a few more bumps and it picked the vibe back up. Oh Brother, a few more and it went away.

The engine sounds like its running ok, doesnt appear to be lean. It almost acts like a bent spindle but the blades dont go out of track.

Anyway I tore the entire head apart again and replaced everything including the thrust bearings and I will fly it this afternoon.

Has anyone seen this before ??????

:?:

[Racer38]

Well it appears as though it is in fact engine related, Talked with DR C-Spec himself (ClintStone) and it appears that the mid range was a bit lean, I have been doing some adjusting on it and it is smoothing out real nice and staying that way. I'm amazed that the engine being lean can make the gear shake that much. It was still shaking after the head rebuild, I changed Blades, made sure everything is tight, and there is just no way that this thing should shake at all, but it did.

I'm going to keep playing with the mixtures to get it perfect. I have the restrictor needle on the carb for the return flow and I am guessing that turning this needle in richens the mixture or is it the same as the main needle ? I dont know if it restricts the return flow or not ?

Thanks

Craig :?

[Greg McFadden]

have you checked the bearings in the engine? I had a YS 80 vibrating something fierce unrtil I changed the bearings out

[Racer38]

No but that was next on the list, and since it is actually smoothing up with the carb tuning I'm guessing the bearings are probably Ok.

I plan to do a complete tear down on this thing over the winter and rebuild or repair as needed.

Thanks for the suggestion..

Craig

[Bonsai]

I have seen where one blade being tighter then the other has caused this type of a vibe..
Dean

[Racer38]

Hmmm Interesting, I always try to make sure the blades break free with the same amount of force, and I just changed out blades to make sure I didnt have a mis matched pair but it was still shaking pretty good. So far two flights and a few adjustments on the engine and it appears to be all but gone, it picks up a little shake when the motor is apparently moving through to the low end but not near what it was. I really need to check the engine bearings and make sure they are Ok.

Hey when ya get your HeliFreak Banner how about strapping it on the side of a Camel, that would make for a Great Photo :lol:

I also gave some HeliFreak Bumper Stickers to some friends who are going to put them on thier HMMV's over in Iraq, yet another Good Photo Op !

[Bonsai]

One camel op coming right up..Yhea we are trying to figure out how to get it into some pretty strange places..This shoud be really Fun..Not gonna push it though as it could cause some minor heart burn. :shock:
Dean