HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 05, 2013, 03:48 PM
Registered User
Joined Jan 2013
3 Posts
Help!
Night Vapor engine/prop squeals then looses thrust

I'm a noob here and have just dipped my toe into the hobby for the first time in about 30 years. On day two of my return I have run into a problem with my new Night Vapor. After flying it quite a bit today, I started to hear a chirping sound that varied with throttle setting. While flying it back to where I was standing, the chirp turned into a squeal and then the a/c lost power (still squealing) and descended into the grass. I retrieved it and then slowly advanced the throttle to start troubleshooting. When it just starts to turn, the prop/gears/engine sound fine. At about 10% throw on the throttle, the squeal starts to build and if any more power is added, the airframe shudders and there is a noticeable loss in engine power.

Can anyone point me in the right direction to start replacing parts?
tasksaturated is offline Find More Posts by tasksaturated
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 05, 2013, 04:30 PM
Registered User
Digital Don's Avatar
United States, IL, Manteno
Joined Dec 2006
672 Posts
Is the prop tight on the shaft? If not, it may be cracked or stripped.

If the prop is good, check the gear on the prop shaft for a crack. If it's cracked, it It might work OK up to a point, then start slipping with increased power.

It's also possible that the motor is on the way out.

Hope it's something simple!

Don
Digital Don is offline Find More Posts by Digital Don
Reply With Quote
Old Jan 05, 2013, 05:36 PM
Or current resident
glewis's Avatar
USA, FL, Tampa
Joined Jul 2002
4,749 Posts
Sounds like maybe the nut on the back of the prop shaft is too tight and caused the gear to come loose on the shaft as Don suggested.
Could also be the prop shaft and motor bushings just need some oil.
I've had both of those things happen.

Glenn
glewis is offline Find More Posts by glewis
Reply With Quote
Old Jan 05, 2013, 11:37 PM
Micro enthusiast
Groovechampion's Avatar
Australia, SA, Adelaide
Joined Aug 2011
771 Posts
My umx spitfire motor did the same thing recently. I noticed degraded performance on her after only 20 or so flights. The motor let out a loud squeal and the plane glided towards the ground. RC Babbel calls this the scream of death! Anyways my solution was to buy a new motor from RC Babbel.

Regards Nath
Groovechampion is online now Find More Posts by Groovechampion
Reply With Quote
Old Jan 06, 2013, 04:00 AM
Have fun
airpower's Avatar
Joined May 2007
6,088 Posts
Sometimes the motor slides back in the mount and disengages, sometimes the crash pushes it back into place.
airpower is offline Find More Posts by airpower
Reply With Quote
Old Jan 06, 2013, 09:39 AM
Registered User
Joined Jan 2013
3 Posts
Thanks for all the feedback. I took a look at the prop and gears this morning. There was no visible evidence of breakage to I did a static power test. I ran the throttle up slowly until I was at full power and left it there for several minutes. There was no squealing so I'll take it out in a while to do an inflight eval.
tasksaturated is offline Find More Posts by tasksaturated
Reply With Quote
Old Jan 06, 2013, 10:57 AM
Registered User
Terry Rigden's Avatar
UK, Bedworth
Joined Apr 2004
2,571 Posts
Add just a tiny drop of light oil to the shaft and gears - don't over do it

Terry
Terry Rigden is offline Find More Posts by Terry Rigden
Reply With Quote
Old Jan 06, 2013, 02:09 PM
Have fun
airpower's Avatar
Joined May 2007
6,088 Posts
Add a litte glue to the motor so it doesn't slide back. This would happen to me, in the middle of the flight it would squeal and go to zero power. It was the sounds of the motor being unloaded from sliding back. With the night vapor I just shifted the wing right up against the motor to hold it there.
airpower is offline Find More Posts by airpower
Reply With Quote
Old Jan 07, 2013, 05:29 PM
frash
Joined Feb 2006
120 Posts
This has happened to me several times and frequently was difficult to diagnose.

Each time the prop or one of the gears was slipping or the motor had moved so that the gears no longer meshed well.

Fred Rash
frash is offline Find More Posts by frash
Reply With Quote
Old Jan 14, 2013, 06:59 PM
Registered User
Joined Jan 2013
3 Posts
Thanks for all the advice. I haven't had the symptoms return since last week. I guess I over flew it. My new rule is only 2-3 batteries before giving the motor/gears a break.
tasksaturated is offline Find More Posts by tasksaturated
Reply With Quote
Old Feb 12, 2013, 11:16 PM
Registered User
United States, CA, Thousand Oaks
Joined Apr 2009
554 Posts
Quote:
Originally Posted by tasksaturated View Post
Thanks for all the advice. I haven't had the symptoms return since last week. I guess I over flew it. My new rule is only 2-3 batteries before giving the motor/gears a break.
If it happens again, call Parkzone. Bob
wslco10 is offline Find More Posts by wslco10
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Night Vapors & Vapors at HHAEFI Dave Burrow Hodges Hobbies All Electric Fly-In (HHAEFI V7) 4 Sep 19, 2012 07:03 AM
Found Vapor or night Vapor good condition with TX sst2000 Aircraft - Electric - Micro & Indoor Airplanes (FS/W) 1 May 31, 2012 06:16 AM
For Sale BNF Parkzone Night Vapor 1 mo. old w/ carbon props The RevKev Aircraft - Fuel - Airplanes (FS/W) 4 May 01, 2012 11:09 PM
Discussion vapor to night vapor wings... karfrik Micro Ready-to-Fly 0 Mar 26, 2012 05:44 PM
Help! Parkzone Vapor and night Vapor Prop? bakon Scratchbuilt Indoor and Micro Models 10 Apr 15, 2011 05:45 PM