Video and photos: Whiplash gasser chirping, tail shake, and /r nah nahs

[rhodesengr]

edit: see photos of parts below.

We've been discussing Whiplash Gasser chirps, nah nahs, and tail shaking in another thread. Before I take my Whiplash apart to send the clutch bell in for pinning, I wanted to post a video of exactly what my Whiplash is doing. I'd like to get some advice on whether this is the symptom that is fixed by pinning the OWB or if it is some other cause. I found I could trigger the chirping and tail oscillation most reliably by coming straight down and then reversing back upwards. The chirping and tail shaking usually starts at the moment I switch from down to up. Once the chirping starts, I have to give it positive collective to stop it. I didn't edit the video and there are some sections where the guy with the camera is moving around. Here is some setup up info:
Stock Whiplash with Hanson 3D Max G290:
GV1 governor :Normal 1700, IU1 1800, IU2 1900
BD3SX FBL controller in Rigid.

I found the governor is a factor. It is less likely to happen if the governor is off but I did get the chirping and tail shake with the governor off. The video happens to be with the governor on. I did try higher and lower tail gains and this did not seems to change anything.

Here are some segments of interest.

chirping and tail shake in IU1: 1:15 to about 1:137
chirping and tail shake in IU2: 2:35 to 2:50
chirping and tail shake with heli on the ground. Symptom starts and stops as I move the throttle up and down.

[fastflyer20]

OWB is slipping

Clutch is secondary, but may be slipping too, the OWB is bad enough to possibly mask clutch issues

Also sounds rich in a hover

[rhodesengr]

Originally Posted by fastflyer20

OWB is slipping

Clutch is secondary, but may be slipping too, the OWB is bad enough to possibly mask clutch issues

Also sounds rich in a hover

so how to fix? Is this the slipping that is fixed by pinning the outer race or is the slipping between the sprags and the pinion? In which case how do you fix that? Clean and lube with ATF?

Just want to add that this model is about four months old and has done this from the beginning.

[fastflyer20]

Some OWB work good and some don't. Yours sounds pretty bad. It can be a combo where a contaminated clutch can help start a chain reaction.

I have found the undersized pins fix the clutch, MA could look at the bell/OWB for you but make sure you remove all lube and just add a few drops of ATF or the clutch will become contaminated.

[Chickens2252]

My tail control rod squeaks, bad as it moves through the guides. It hasn't caused a wag yet. But just for peace of mind I've adjusted them and put some 100% silicon grease on the rod. You might try lubing your rod and see what it sounds like then.

Probably a moot suggestion if you've already sent off your clutch.

[Calil]

Originally Posted by fastflyer20

OWB is slipping

Clutch is secondary, but may be slipping too, the OWB is bad enough to possibly mask clutch issues

Also sounds rich in a hover

Sorry to ask but what does OWB means?

[breakout]

one way bearing

[Calil]

Originally Posted by breakout

one way bearing

Thank you!

[goof2]

Just something else to think about but it doesn't seem to do it under load. So yes the bearing could be slipping but maybe the motor is a little rich. When you unload it gargles for a bit till you load it again.

Does the tail hold on a full power climb? If you fly it hard do you notice the problem or is it only when unloading?

[dodgeboy]

I had the very same noise. Today im going to see if a new pinned bell is the fix. I'll report back.

[LoveToFly1]

That's is exactly what mine was doing. Yours seems much worse than mine was. Tom is exactly right about the clutch slipping and the owb being a chain reaction. Send thst bell in and at the very least clean that clutch up very well. I took my clutch shoes and cleaned them with acetone, then took some old light grit sandpaper and scuffed them up good.

I have put close to a gallon through my whiplash this weekend so far (in ga at a fly in) and I have only had this happen once or twice all weekend. I have notkinstalled the under sized pins in the clutch yet though (they came in the night before we left and I already had helis packed up) so I am assuming the clutch slipped a tad when it happened. I will instal the pins when back home though and see how that goes.

I know its odd, you would think all these parts would slip when loaded up, not when unloading. But i have seen weirder things happen with helis......

[rhodesengr]

so if you see what I said in my post. The onset is not exactly when unloading. It starts when I reload lightly after an unload. To get the chirping to start, I would descend and then gently reverse up. If I reverse up hard, it is less likely to start.

So the picture I have is like this: coming down, the OWB disengages because the blades spin a little faster than the motor. Then when I gently reverse up the OWB has to engage again but there is not a lot of torque so the engagement is intermittent. If I hit the collective hard, there is a lot of torque and the OWB makes a solid engagement. If you notice in the video and watch the whole thing, on that flight it did no happen every time. When I switched to IU2, I had to try three times to get the effect. It was more noticeable on the ground. As I add throttle gently, the effect starts.

[rhodesengr]

Here are some photos of the parts as they came apart this evening. I found the inside of the bell and the clutch shoes covered in thick, gray, grease-like substance. I didn't use anything like that in assembly. No sign it came out of the engine top, The starter OWB below, I cleaned before assembly and applied some ATF. The bell assembly, I used right as it came from the box. The pinion looks like it got hot in the sprag area.

Curious if anyone else has seen gray grease inside their clutch bell.

inside of clutch bell with gray grease. I wiped one lien with a q-tip to show the difference.


top of the bell look unremarkable. Maybe some discoloration on the sprag teeth


top of the engine with clutch. Clutch pads have the gray stuff but so sign of it elsewhere.



clutch pad 1


clutch pad 2



pinion looks like it took some heat in the sprag area.

[fastflyer20]

The bell/OWB lube contaminated the clutch.

[LoveToFly1]

I too found the same grease. I didn't assemble the clutch originally so I cleaned it off and re installed. I only used a few drops of triflow on my sprag. I flew nearly a gallon through it this weekend.....I took heli back apart to instal the new undersized bushings last night and noticed a TINY TINY amount of what seemed to be the same grease on the bell. Again, I didn't use black grease when installing the clutch last time.... the shoes had a little grease on them to. So I cleaned and re installed.

I have seen a similar looking substance before....just a few weeks ago when my sealed bearing went bad on my 231....the substance that was coming out of the crankcase looked similar to this. It was the white packing from inside the bearing turned black/grey from the oil in the crankcase. When hanson fixed that motor up he left the sealed bearing off and installed another true seal instead. He said he would be doing this on all of his heli motors from now on since the clutch provides support for that side of the motor. I hope the grease is the triflow getting hot and not the bearing grease though.....I'm tired of breaking in motors! Lol

[rhodesengr]

Originally Posted by fastflyer20

The bell/OWB lube contaminated the clutch.

So is that another design issue? I just used the parts right out of the box. I would think it should be designed so that the OWB lube stays in the OWB. What prevents this from happening over and over? Pinning the OWB won't change how the lube moves around.

[fastflyer20]

Posted in a few other Whip/gasser threads, pop the brass washer, remove OWB, degrease and reassemble. Use a few drops of ATF. Now there is not enough lube to leak into the clutch.

I tried sealing with o-rings, but this works better.

[rhodesengr]

Originally Posted by fastflyer20

The bell/OWB lube contaminated the clutch.

Tom,
On further thought and review of the photos, I am not so sure the gray stuff comes from the sprag or other bearings above the clutch. Notice how the inside top surface is totally clean. The gray stuff is only on the clutch pads and pad engagement area in the bell. If the lubricant was migrating down from above, it would have to spin out across the inside top surface and it does not appear to have done that.

Maybe another possibility if some sort of breakdown of the clutch pad material. Since it is a Zenoah part, what do we really know about its makeup? Jeff at MA tells me he sees this in many bells that come back to him.

Any recommendations about how to best clean the gray stuff off the clutch pads?

[fastflyer20]

Sorry, I stand by my theory, been there and done that.

Jeff keeps seeing it because they keep over lubing.

[Doug Darby]

Acetone cleans the shoes very nicely..