Go Back  RCU Forums > Glow Engines, Gas Engines, Fuel & Mfg Support Forums > Glow Engines
Reload this Page >

OS 1.20AX Unexplained Flameouts.......>>>

Notices
Glow Engines Discuss RC glow engines

OS 1.20AX Unexplained Flameouts.......>>>

Old 07-30-2012, 03:02 AM
  #51  
dodgers72
My Feedback: (1)
 
Join Date: Jun 2004
Location: Bargersville, IN
Posts: 60
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

I had a fuel foaming problem in my GP minnow because the tank was hard mounted. Used a perry pump relocated the tank closer to the balance point where I could soft mount it easier it worked great and the bonus is it doesn't change balance throughout the flight. Just a thought if all else fails.


Chris
Old 07-30-2012, 03:21 AM
  #52  
w8ye
My Feedback: (16)
 
w8ye's Avatar
 
Join Date: Dec 2001
Location: Shelby, OH
Posts: 37,576
Received 8 Likes on 8 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Several years ago I fought a OS 120AX for twoi seasons. I never did resolve the FLAMEOUTS problem. Never had any trouble with other two strokes but the 120AX.

My solution was to replace is witha OS 160. - - - No more flame outs!


Old 07-30-2012, 05:20 AM
  #53  
dingo9882
 
Join Date: Apr 2005
Location: Southbury CT
Posts: 286
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Sounds like a bad bearing....mine did the SAME EXACT THING...and it was a bad rear bearing. The way I found out was when the prop just stopped dead because the bearing race got sucked up into the piston.
Old 07-30-2012, 05:21 AM
  #54  
1QwkSport2.5r
 
1QwkSport2.5r's Avatar
 
Join Date: Oct 2006
Location: Cottage Grove, MN
Posts: 10,228
Received 58 Likes on 55 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Foam/felt clunks were brought up earlier in the conversation but I doubt it will flow enough fuel for a 120. I use felt clunks from the chainsaw shop and they work fine on all of my engines except my SuperTigre S90. The needle could be removed while the engine ran (plugged hole with finger) and the engine was still running lean. Replaced the clunk with a standard one and it needled fine.

My only thoughts are a lack of muffler pressure or an air leak. Or maybe the engine is just no good?
Old 07-30-2012, 05:28 AM
  #55  
dingo9882
 
Join Date: Apr 2005
Location: Southbury CT
Posts: 286
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

I want to add one more thing. Mine would fly great for like 2 or 3 flights. THen all of a sudden it would flame out. I changed the fuel and the same thing happend. I changed needle setting, tubing, glow plugs and piston rings. It got bad enough that I crashed the plane because of a flame out and when I replaced the plane it kept on happening. Thats when the bearing went, and this time it was on the ground just running it dry. It only had 50 or so flights on the engine too. Since then I have replace the engine bearings twice. THe engine just eats bearings, so I went and bought high performance ones now and everything is much better. CHECK that bearing. The problem is its hard to tell because the front bearing was masking the problem becauase of the tight tolerances.
Old 07-30-2012, 06:22 AM
  #56  
flycatch
Senior Member
My Feedback: (26)
 
Join Date: Jul 2002
Location: Barstow, CA
Posts: 2,021
Likes: 0
Received 6 Likes on 5 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

I'm no engine mechanic but it appears all that is necessary is to adjust mid range meter setting.
Old 07-30-2012, 06:29 AM
  #57  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: flycatch

I'm no engine mechanic but it appears all that is necessary is to adjust mid range meter setting.
Son of a gun... I must have missed that. Thanks.

Old 07-30-2012, 07:49 AM
  #58  
airraptor
My Feedback: (66)
 
Join Date: Jan 2004
Location: fairfield, CA
Posts: 4,191
Likes: 0
Received 2 Likes on 2 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: flycatch

I'm no engine mechanic but it appears all that is necessary is to adjust mid range meter setting.

lol really that will fix all my engines too.

try one other thing. get another fuel tank. take cowl off and put the tank on the firewall and mount box. now run the engine on the ground with this new tank or known working tank. if runs well on this one then the tank is the issue.

now the bearings o nthese engines are crap. same one as the OS140 crap. If the bearing is going bad the the glow plug will be burning out also.

If it still does this with the new tank then its engine related.
Old 07-30-2012, 07:50 AM
  #59  
Captain Terrific
Senior Member
My Feedback: (2)
 
Join Date: Jun 2010
Location: Chesapeake, VA
Posts: 138
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

I'll be interested in your findings.

Dave
Old 07-30-2012, 08:20 AM
  #60  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: airraptor


ORIGINAL: flycatch

I'm no engine mechanic but it appears all that is necessary is to adjust mid range meter setting.

lol really that will fix all my engines too.

try one other thing. get another fuel tank. take cowl off and put the tank on the firewall and mount box. now run the engine on the ground with this new tank or known working tank. if runs well on this one then the tank is the issue.

now the bearings o nthese engines are crap. same one as the OS140 crap. If the bearing is going bad the the glow plug will be burning out also.

If it still does this with the new tank then its engine related.
I ordered in a 2oz header tank this morning. I'll give it a shot. I'll try anything at this point!

I am going to try the stock powerbox muffler next weekend without any other changes. If that does not work I will add the header tank. If that doesn't work, I will add the brand new YS 1.15 I purchased this morning. That'll show that big finicky OS.... LOL!



Old 07-30-2012, 08:24 AM
  #61  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: Captain Terrific

I'll be interested in your findings.

Dave
Me too Dave, because right now I have spent more time and effort on this issue than ALL the combined issues I have ever had in 30+ years of being in the RC hobby!
I have NEVER had an issue that I couldn't resolve like this one. My builds and installs are quite honestly first rate. I don't skimp on anything and I generally do not ever miss a detail. Not to sound boastful, I am just a detail oriented freak. Even the guys at my field bust my chops because my little 30cc MX2 has more thought, design & technology into it than most guys 150cc planes. It's just the way I am. I build them right so Sunday can be fun, enjoyable and safe. This one has me baffled...

Old 07-30-2012, 08:36 AM
  #62  
tony0707
 
Join Date: Jul 2006
Location: Inverness, FL
Posts: 963
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

hi
Touch the head as soon as you landjust tap itbe carefull see if it is hot or cool
if cool i think you are running TOO richit will snuff out the glo plug
if hot you are too leannot likely with a good smoke trail
Pinch the fuel line on the top end -running full bore the engine will screem up to max RPMthe increase should only be 2-300 RPMS no more
you can do the same thing at an idlerun up should be just a little or the low end is not right
if more of a run up than a little you are to rich
be sure the pressure fitting on the muffler is clean
Check to see if the brass fuel lines have cut the fuel tubingdo not leave the tubing ends sharp
Dead stiks are no fun !
if you fly for the same amount of time before the engine dies it could be an internal tank problem
if you had a HARD landingyour clunk could be jamed to the front of the tankshake the plane and listen for the clunks movement
my last suggestion could be your problem
i choose to fly my planes that have a cowlwith no cowl on a maiden or early flights until i am sure the engine is set up and running perfectthen the cowl goes onusually only require a slight trim adjustment with the cowl back on
flying only two cycle glo for 22 years more than most
Regards Tony
Old 07-30-2012, 08:49 AM
  #63  
NM2K
Senior Member
My Feedback: (14)
 
Join Date: Jan 2002
Location: Ringgold, GA
Posts: 11,488
Likes: 0
Received 2 Likes on 2 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: dodgers72

I had a fuel foaming problem in my GP minnow because the tank was hard mounted. Used a perry pump relocated the tank closer to the balance point where I could soft mount it easier it worked great and the bonus is it doesn't change balance throughout the flight. Just a thought if all else fails.


Chris


Well, burning off fuel as the flight progresses does change the trim of the model. The heavier the model is, the higher the angle of attack (or incidence, I forget which is proper) the wing must fly to develop a given amount of lift. While locating the fuel tank at the balance point is a help, it does not completely eliminate the changing of the trim as the fuel burns off.

Anyway, I'm glad that you solved your immediate problem.


Ed Cregger
Old 07-30-2012, 09:48 AM
  #64  
airraptor
My Feedback: (66)
 
Join Date: Jan 2004
Location: fairfield, CA
Posts: 4,191
Likes: 0
Received 2 Likes on 2 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

duh i think i have it now lol

I forgot you had a pitts muffler lol. I am not sure it was covered but i bet your not getting enough back pressure from the pitts muffler to supply the engine once the tank gets low. block off one of the muffler outlets and bet it will cure it!!!
Old 07-30-2012, 09:48 AM
  #65  
Firepower R/C
My Feedback: (10)
 
Join Date: Nov 2004
Location: Bloomington, IL
Posts: 564
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Taz, did you ever try blocking off one exhaust on your pitts muffler? I know others have mentioned it, but I didn't see that you actually tried it (maybe I missed it). I would bet that fluxuating pressure is your problem, given that you checked other things. I bet the mixture is fine at full throttle on the ground, but the mix leans out too much to support combustion when you back off the throttle. I have had several instances of this happen to me with pitts muffler setups! I actually crimp down the exhausts until I get just enough back pressure to get a good fuel flow at all throttle settings. This adjustment has turned several "headache" engines into my favorites!

p.s. I would pressure test your fuel systems instead of vacuum test... pressure will mimic "in-service" conditions more closely, & tend to open pinholes in the fuel lines, while vacuum will contract the lines and could hold the pinhole shut. If you are already doing this, please disregard!

Good luck and I hope you get it figured out soon!!
Old 07-30-2012, 10:32 AM
  #66  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: Firepower R/C

Taz, did you ever try blocking off one exhaust on your pitts muffler? I know others have mentioned it, but I didn't see that you actually tried it (maybe I missed it). I would bet that fluxuating pressure is your problem, given that you checked other things. I bet the mixture is fine at full throttle on the ground, but the mix leans out too much to support combustion when you back off the throttle. I have had several instances of this happen to me with pitts muffler setups! I actually crimp down the exhausts until I get just enough back pressure to get a good fuel flow at all throttle settings. This adjustment has turned several "headache" engines into my favorites!

p.s. I would pressure test your fuel systems instead of vacuum test... pressure will mimic "in-service" conditions more closely, & tend to open pinholes in the fuel lines, while vacuum will contract the lines and could hold the pinhole shut. If you are already doing this, please disregard!

Good luck and I hope you get it figured out soon!!
I haven't blocked off one of the outlets yet, as in reality a 1.20 is pushing enough exhaust pressure that should not be a problem. On smaller engines I would tend to agree. I am putting the stock powerbox muffler on her this coming weekend to "test" that very theory. And if all else fails, while I was buying the 1.15YS this morning I came across a smoking deal on a 1.20 YS that I couldn't pass up, so if the Big OS doesn't cooperate, she have either a 1.15 or a 1.20 YS on her in the near future!

Oh I did mean to add that when she dead sticks and I retrive her, the fuel line to the carb is fully charged. I realize this may not tell the whole story, but the way she shuts off like someone turned off the fuel petcock, I would have thought the fuel loine would be dry if that was the case.

Old 07-30-2012, 11:10 AM
  #67  
Firepower R/C
My Feedback: (10)
 
Join Date: Nov 2004
Location: Bloomington, IL
Posts: 564
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

The fuel line wouldn't be dry unless the line was sucking air, right (i.e., empty tank, hole, etc.)? That shows that your fuel system should be solid, like you said. Sounds like you are closing it on it, but I would urge you to just try blocking one exhaust stack, since it is so easy. I wouldn't just assume that the 1.20 should have enough push... a bigger engine doesn't assure more muffler pressure. Try wedging a dowel in an exhaust... if it works, you have pinpointed the trouble. I went through this with an Evo 100/pitts combo that made me want to jump off a cliff. Now it is the bomb diggity.

If you either restrict the pitts or install the powerbox, my pesos are on your problem going away. My brother has this engine in a ESM Spitfire, and I think he restricted the exhaust on his pitts. Runs like a top! He gave me the powerbox muffler to try on my JBA 1.20. Anyway... good luck and let us know!!!


LONG LIVE GLOW!!! couldn't resist
Old 07-30-2012, 11:11 AM
  #68  
flycatch
Senior Member
My Feedback: (26)
 
Join Date: Jul 2002
Location: Barstow, CA
Posts: 2,021
Likes: 0
Received 6 Likes on 5 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

I have run both two and four cycle engines for many years and most of not all problems is fuel metering. Either too much fuel or not enough entering the carburetor. Leaning and riching the fuel/air mixture ratio is the key issue for any set-up.
Old 07-30-2012, 12:03 PM
  #69  
Prop_Washer2
My Feedback: (26)
 
Join Date: Aug 2003
Location: El Paso, TX
Posts: 677
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Me too..!! It's like having onboard battery support..!! I did notice that my Tower .75 did not like the "F" Plug, when it got really spun up on a downwind leg, the motor would "miss". I put a Supertiger run of the mill cheap plug, runs great...


ORIGINAL: RCPAUL

I use an "F" plug in all my engines 0.60 and above - especially STs. Sounds to me like a tank, fuel line problem. Pin hole? I also add a little castor to my fuels and never use less than 18% oil.

Paul
Old 07-30-2012, 01:08 PM
  #70  
airraptor
My Feedback: (66)
 
Join Date: Jan 2004
Location: fairfield, CA
Posts: 4,191
Likes: 0
Received 2 Likes on 2 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: flycatch

I have run both two and four cycle engines for many years and most of not all problems is fuel metering. Either too much fuel or not enough entering the carburetor. Leaning and riching the fuel/air mixture ratio is the key issue for any set-up.

really did you just say that lol little slow huh.
Old 07-30-2012, 07:12 PM
  #71  
tevans55
 
Join Date: Aug 2007
Location: Louisville, KY
Posts: 1,337
Received 4 Likes on 4 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Taz-
I have a 120 AX in my ESM Spitfire. I have it mounted inverted with a JTEC wrap around Pitts muffler. Most has already been said. I had to relocate pressure nipple. I also had to run the engine in my driveway for about 10 hours to break it in. The most stubborn glow engine I ever dealt with. I would run for about an hour and think it was ready to go and the next day I would fire it up and it was like I had never adjusted the engine. I have several twins so I always spend alot of time with breakin on the ground until I am assured of reliability. You may have run into the same situation I did...it may just need more run time. I found the #8 plug works best...this engine develops a lot of heat and the Spitfire cowl is as tight as they come. Good Luck with your patience!
Attached Thumbnails Click image for larger version

Name:	Rp44399.jpg
Views:	32
Size:	67.2 KB
ID:	1787786  
Old 07-30-2012, 08:47 PM
  #72  
bjbellino
My Feedback: (176)
 
Join Date: Dec 2003
Location: florence, CO
Posts: 124
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Had trouble getting a O.S. 55 nitro to run, had a pitts muffler, engine did not want to idle well and ran fair at full throttle. Had heard that the pitts exhaust would not allow enough tank pressure to get engine to run well, was suggested to plug off one of the down tubes on the Bison muffler, but had enough room to go back to stock O.S. muffler and it seemed to cure a lot of problems, Good luck, Bob.
Old 08-01-2012, 07:17 AM
  #73  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: tevans55

Taz-
I have a 120 AX in my ESM Spitfire. I have it mounted inverted with a JTEC wrap around Pitts muffler. Most has already been said. I had to relocate pressure nipple. I also had to run the engine in my driveway for about 10 hours to break it in. The most stubborn glow engine I ever dealt with. I would run for about an hour and think it was ready to go and the next day I would fire it up and it was like I had never adjusted the engine. I have several twins so I always spend alot of time with breakin on the ground until I am assured of reliability. You may have run into the same situation I did...it may just need more run time. I found the #8 plug works best...this engine develops a lot of heat and the Spitfire cowl is as tight as they come. Good Luck with your patience!
Great looking bird, I can't imagine the anxiety flying her knowing the engine may conk out at any moment.

I have completely fixed my issues! I figured out the problem and I am fixing it...

The big OS is going bye bye and the YS 1.10FZ I have on a Funtana S90 is going in the Ultimate. The Funtana needs so much nose weight to balance, I am putting in a brand new YS 1.20SF (yes, an older style/version but brand new in the box) that is heavier on the Funtana and the 1.10FZ in the Ultimate. I really love the way the Ultimate flies and I want to enjoy it to the fullest and not worry about the OS issues. New cowl is sitting next to the Ultimate and I will get to work on that tonight, time permitting.

Old 08-01-2012, 01:28 PM
  #74  
daveopam
My Feedback: (9)
 
daveopam's Avatar
 
Join Date: Oct 2002
Location: ELK CITY, OK
Posts: 7,777
Received 38 Likes on 33 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>

Wanna sell or trade the big OS? It would have to be worth the money.


David
Old 08-01-2012, 03:32 PM
  #75  
Taz_Hobbies
Senior Member
Thread Starter
My Feedback: (15)
 
Join Date: Oct 2011
Location: Spring Hill, FL
Posts: 281
Likes: 0
Received 0 Likes on 0 Posts
Default RE: OS 1.20AX Unexplained Flameouts.......>>>


ORIGINAL: daveopam

Wanna sell or trade the big OS? It would have to be worth the money.


David
Sure Dave, make me a reasonable offer. It will come with the Pitts Muffler, the stock powerbox with both adapters. I am always in need of cash for other projects.


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.