Flameouts on Take-Off, ST3000    Gallery
View related threads: (in this forum | in all forums)

Logged in as Guest



Users viewing this topic: none
    Search This Thread  
 
Printable Version

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Manufacturers Direct Support Forum >> SuperTigre Engines Support >> Flameouts on Take-Off, ST3000
Page: [1]

Tower Hobbies Get Coupon Codes Brands  
Login
Message << Older Topic   Newer Topic >>
Flameouts on Take-Off, ST3000 - 7/11/2011 11:11 PM   
redball8



Posts: 162
Score: 125
Joined: 12/14/2003
Last Login: 6/17/2013
From: Naperville, IL, USA
Status: offline 		Every third or fourth flight the ST3000 on my 38.5% Corby Starlet will "flame-out" - taxies out to the runway just fine, throttles up well and then maybe 10 seconds after full throttle she dies. The OS 7D carb seems to be set just fine, great transition & steady idle at ~1700 rpm. Engine runs wide-open throttle at about 300 rpm off peak (7400 rpm), running a fairly high-oil fuel for break-in (~7% nitro, 16% oil with 50/50 castor/synthetic). 18x8 prop, Hangar 9 3011 (four-stroke) plug, all large size fuel tubing, clunk drilled out, large filter, Bisson pitts muffler. I can have 2-3 flights and she runs strong, then a flameout and things get exciting.

I'm wondering if perhaps I'm setting the high-speed needle a bit too lean? Something new for me is how the larger engines react once airborne and unloaded; I really notice too rich a HS needle setting as a lack of power, and think perhaps the flameouts tell me she's too lean?

Thanks,
RB8

Hide Signatures
       Post #: 1

RE: Flameouts on Take-Off, ST3000 - 7/12/2011 3:30 PM   
Bax


 

Posts: 17344
Score: 169
Joined: 4/26/2002
Last Login: 6/19/2013
From: Champaign, IL, USA
Status: offline 		Well, with the non-SuperTigre carb, we'd not really be able to comment much, even if it's an O.S. carb. It's just not one that's made for the engine. That aside, if the engine cuts clean, it's just too lean. The engine's not getting fuel. You should check to make sure you have large-size fuel tubing running from the clunk to the carburetor. Many fuel tanks have regular-size tubing inside, and the large glow engines need bigger tubing. Even on a 20-ounce tank, we re-plumb the tank to large brass tubing, larger silicone tubing, and we drill-out the clunk. You also need to make sure your muffler is giving good pressure to the tank. Many after-market mufflers just don't have much pressure to deliver to the tank.

You may also want to increase the idle RPM a bit. A too-low idle RPM will result in the carburetor getting unbalanced regarding the high-speed and low-speed mixtures. A too-low idle will likely mean that the idle mixture's too lean. This will cause fuel flow problems at full throttle.



_____________________________

Bill Baxter, Manager Hobby Services/Futaba Service/North America
3002 N. Apollo Dr. Ste. 1 Champaign, IL 61822 USA
Service Phone: 217 398-0007
Email: hobbyservices@hobbico.com

Hide Signatures

(in reply to redball8)
       Post #: 2

RE: Flameouts on Take-Off, ST3000 - 7/12/2011 8:05 PM   
redball8



Posts: 162
Score: 125
Joined: 12/14/2003
Last Login: 6/17/2013
From: Naperville, IL, USA
Status: offline 		I think you hit the nail on the head, Bax! I had become enamoured with low idle, put an onboard glow unit on the motor and had been running as low as 1400 rpm. There is definitely an interaction. Should I try the idle at say 2000 rpm?

Thanks very much,
RB8

Hide Signatures

(in reply to Bax)
       Post #: 3

RE: Flameouts on Take-Off, ST3000 - 7/13/2011 3:05 PM   
Bax


 

Posts: 17344
Score: 169
Joined: 4/26/2002
Last Login: 6/19/2013
From: Champaign, IL, USA
Status: offline 		2000 RPM is a good number. We consider anything under 2,500 as "good". You may also need to check to be sure the clunk isn't too close to the back of the tank. Under acceleration, the fuel is forced to the back. If the clunk is too close, it actually "sees" higher fuel pressure and can flood-out the engine, but only during the initial acceleration of the takeoff roll.

_____________________________

Bill Baxter, Manager Hobby Services/Futaba Service/North America
3002 N. Apollo Dr. Ste. 1 Champaign, IL 61822 USA
Service Phone: 217 398-0007
Email: hobbyservices@hobbico.com

Hide Signatures

(in reply to redball8)
       Post #: 4

Page:   [1]
All Forums >> Glow Engines, Gas Engines, Fuel &amp; Mfg Support Forums >> Engine Manufacturers Direct Support Forum >> SuperTigre Engines Support >> Flameouts on Take-Off, ST3000
Page: [1]





Jump to:


 
Google 



Search | Marketplace | Event Calendar | Local Clubs | Magazine | Product Ratings | New Products | Discussion Forums

Photo Gallery | Instructor Search | Field|Track|Marina Search

Advertisers | Hobby Vendor Resources | Rate Manufacturers | Sign In/Sign Up

SITE MAP!   : :   FORUM RULES

RC Universe is a service of Internet Brands, Inc. Copyright © 2001-2013.

Charities we support that also need your help
Yorkie Rescue | Humane Society | ASPCA | Crohn's-Colitis America


0.391RCU1