OS 70 Ultimate carb question / solution  
View related threads: (in this forum | in all forums)

Tower Hobbies
Enter up to 4 keywords or Tower stock numbers
Logged in as Guest



Users viewing this topic: none
  Printable Version
       

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Manufacturers Direct Support Forum >> O.S. Engines Support >> OS 70 Ultimate carb question / solution
Page: [1]

Login
Message << Older Topic   Newer Topic >>
OS 70 Ultimate carb question / solution - 6/26/2008 4:15:07 AM   
gibb


 

Posts: 108
Joined: 1/26/2002
From: Livonia, MI, USA
Status: offline 		Bax,

I understand that there were some pump vaporization issues with early build engines.

I bought two of these engines in 2006 from Tower. After 20 or so flights, one of the engines started running leaner and leaner and would surge. Eventually, it was impossible to start the engine especially after it was warm. After much trial and error, I was able to completely fix this problem with a replacement of the regulator diaphram on the carb body. As a side note, I was able to replicate the issue by reinstalling the old diaphram on the engine. Essentially, I could turn the problem on and off by changing this one part even though I could not find anything visibly wrong with the diaphram.
Unfortunately, the diaphram is only sold as an assembly to the carb body ($40 plus shipping). Anyway, I tossed this issue to bad luck and began flying the plane again after installing a new part.

After another 20 or so flights, the same problem started to show again. Slowly the engine started to run leaner and leaner until it would surge. Eventually, not starting.
Once again, I was able to replicate the issue by replacing the regulator diaphram and the engine now runs perfectly again. However, this has now cost me an additional $46 since OS just raised prices.
I now have spent $600 on engines and $86 bucks for diaphrams and am very concerned that this will happen again.

Clearly the fuel vaprization (or some other problem) is damaging the diaphrams. Although I doubt OS will do anything about this, I do wish to buy a bunch of diaphrams instead of entire carb bodies for this engine.

Can you help?

Jim Gibboney
Livonia, Mi
       Post #: 1

RE: OS 70 Ultimate carb question / solution - 6/26/2008 3:30:49 PM   
Bax


 

Posts: 12457
Joined: 4/26/2002
From: Champaign, IL, USA
Status: offline 		Regulator diaphragms are not available from O.S. as separate parts. Even we don't have them. The regulator usually had difficulties if it gets any kind of petroleum product, or if the fuel has oil that is congealing between flying sessions. If the regulator's working correctly, the fuel cannot be vaporizing before it enters the carburetor venturi.

_____________________________

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

(in reply to gibb)
       Post #: 2

Page:   [1]
All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Manufacturers Direct Support Forum >> O.S. Engines Support >> OS 70 Ultimate carb question / solution
Page: [1]





Jump to:


Google 



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

Photo Gallery | Member Video Posts | RCU Video Gallery | Instructor Search | Field|Track|Marina Search

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

SITE MAP!   : :   FORUM RULES

© 2001 - 2007 24-7 RC, LLC, all rights reserved.

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

Kaango.com Classifieds

0.563RCU1