OS 140RX Need Help
08-08-2009, 09:06 PM
#1
OS 140RX Need Help
I’m trying to get a plane going to make the Quincy, OH contest next weekend…
When running at idle or the engine isn’t running, fuel leaks out of the carb. I can get it started, but loads up in about ten seconds and bogs down and dies when increasing the throttle…
If I pinch the fuel line, it leans out and recovers. As long as I stay near full throttle it’s fine…When at half throttle and lower it will bog down….
HS needle is at about 1-3/4 out leanedit was aboutabout 2 turns out before I leaned it a bit. I don’t know the pump settings. Tank sits on the cross brace under the canopy above the wing tube in a Temptation.
This is a used engine already installed in a plane…
Is it just a matter of the pump pressure being too high or do I have other problems to deal with…???
Larry Diamond
NSRCA 3083
08-08-2009, 09:13 PM
#2
RE: OS 140RX Need Help
make sure the main bearing is silky smooth...... rough or unreliable idle is often the main bearing going out.
Can you reset the idle via the idle adjustment screw. It is pretty sensitive but it usually is set just to the right of center of the total throw.
Woodie
Can you reset the idle via the idle adjustment screw. It is pretty sensitive but it usually is set just to the right of center of the total throw.
Woodie
08-08-2009, 09:20 PM
#3
RE: OS 140RX Need Help
When I get it lean by pinching the fuel tube it will transition ok until it loads up again…
Is this consistent with the main bearing? I have a set of bearings to install if needed…Would rather not, unless this is the cause…
Larry
08-08-2009, 09:33 PM
#4
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RE: OS 140RX Need Help
Hi Larry,
Don't Touch The Pump! You'll never get it right again. The instruction say not to touch it. Did you lean the bottom end?
I have one of these and will see you at Quincy. Not really sure what the problem is but the people in the know say never touch the pump. If you need help, Verne Kesster will be there along with Dennis Bodary. These guys are really experienced with this motor and wll be glad to help. I can be reached tonight at work at 1-800-1856-1856EX8096. Call if you like.
RC11 Rick Cilles See you at Quincy in what class?
Don't Touch The Pump! You'll never get it right again. The instruction say not to touch it. Did you lean the bottom end?
I have one of these and will see you at Quincy. Not really sure what the problem is but the people in the know say never touch the pump. If you need help, Verne Kesster will be there along with Dennis Bodary. These guys are really experienced with this motor and wll be glad to help. I can be reached tonight at work at 1-800-1856-1856EX8096. Call if you like.
RC11 Rick Cilles See you at Quincy in what class?
08-08-2009, 10:21 PM
#5
My Feedback: (85)
RE: OS 140RX Need Help
I am assuming this engine has sat for a while since running.
Try injecting some straight methanol into the pump line. Just in case the pump is gummed up from congealed oil.
Doesn't matter on the methanol even denatured alchohol will work.
Not sure what type of plug you have. Either a OS F type/YS 4-stroke plug work equally well. I have not had any luck with the A5 that comes standard with it.
Do not take the pump off the backplate. Bad @%$# happens as that opens up the pump just leave it on the backplate.
Try injecting some straight methanol into the pump line. Just in case the pump is gummed up from congealed oil.
Doesn't matter on the methanol even denatured alchohol will work.
Not sure what type of plug you have. Either a OS F type/YS 4-stroke plug work equally well. I have not had any luck with the A5 that comes standard with it.
Do not take the pump off the backplate. Bad @%$# happens as that opens up the pump just leave it on the backplate.
08-08-2009, 10:27 PM
#6
RE: OS 140RX Need Help
I have not done anything other than adjust the HS needle...
I'll try replacing the main bearing...
Dennis, Im caught between getting this going and/or trying to get the Titan airborne. If I get the Titan going and you want the plane, I may wish to use the Titan until I get the Temptation sorted out...
Thanks for the help...
I'll try to replace the main beiring and see wear it goes...Is fuel leaking out of the carb a normal thing?
Larry...
I'll try replacing the main bearing...
Dennis, Im caught between getting this going and/or trying to get the Titan airborne. If I get the Titan going and you want the plane, I may wish to use the Titan until I get the Temptation sorted out...
Thanks for the help...
I'll try to replace the main beiring and see wear it goes...Is fuel leaking out of the carb a normal thing?
Larry...
08-08-2009, 10:33 PM
#7
RE: OS 140RX Need Help
ORIGINAL: RC11
RC11 Rick Cilles See you at Quincy in what class?
RC11 Rick Cilles See you at Quincy in what class?
LOL
Larry...
PS...So if I show up with a dead plane, you feel we can get it going to make it worth the trip...? 5 hour drive...We'll get there late Friday night, early Sat morning....
08-08-2009, 10:35 PM
#8
My Feedback: (85)
RE: OS 140RX Need Help
Normally the carb will not leak fuel. like i said earlier try injecting alchohal into the pump line first.
Go ahead with flying the Titan it does'nt matter to me, as i may or may not want it anyways.
Are you going to be replacing the bearing with a stock bearing or the orange sealed bearing?
Go ahead with flying the Titan it does'nt matter to me, as i may or may not want it anyways.
Are you going to be replacing the bearing with a stock bearing or the orange sealed bearing?
08-08-2009, 10:40 PM
#9
RE: OS 140RX Need Help
I believe I only have the OS bearing NIP...
That may get me through the day...
Turning a 4 blade 15 x 12 or 11...I'll neeed to look for sure ...
I will try to replace it tonight...Any tips? Never had this engine before...
Larry
That may get me through the day...
Turning a 4 blade 15 x 12 or 11...I'll neeed to look for sure ...
I will try to replace it tonight...Any tips? Never had this engine before...
Larry
08-08-2009, 11:01 PM
#11
My Feedback: (85)
RE: OS 140RX Need Help
Well the stock OS# is 46030008
The CFI bearing # is 29430010 This is the one you want if at all possible. If you are using the unsealed one it will work just won't last any where near as long.
As far as changing the bearing it is the same as replacing any typical OS bearing.
The one big difference is the piston ring. it has to be lined up with the pin in the ring groove otherwise the ring will not compress enough to put the sleeve over the piston.
Leave the hammer in the toolbox. if you have it lined up correct the sleeve will smoothly go over it. It's a PIA but after two minutes you should have it.
As far as the needle valve go on Tower's website Look for the parts for the OS140RX and they show the two different needles. should be able to tell which one you have by the pictures.
One other thing the key for the prop washer only goes in one way the flat side to the engine.
The CFI bearing # is 29430010 This is the one you want if at all possible. If you are using the unsealed one it will work just won't last any where near as long.
As far as changing the bearing it is the same as replacing any typical OS bearing.
The one big difference is the piston ring. it has to be lined up with the pin in the ring groove otherwise the ring will not compress enough to put the sleeve over the piston.
Leave the hammer in the toolbox. if you have it lined up correct the sleeve will smoothly go over it. It's a PIA but after two minutes you should have it.
As far as the needle valve go on Tower's website Look for the parts for the OS140RX and they show the two different needles. should be able to tell which one you have by the pictures.
One other thing the key for the prop washer only goes in one way the flat side to the engine.
08-09-2009, 08:52 AM
#13
My Feedback: (45)
RE: OS 140RX Need Help
Rick,
Verne wont be there, he will be either on his way, or in Portugal for the worlds.
Larry,
The other thing worth trying it find a setting that it will run at and just let it run for as long as you can. It might just need time. It might have gunk the pump or whatever. Also, lean the low end some, but it might just need run. The diaphram might be stiff and just needs sometime,
Arch
Verne wont be there, he will be either on his way, or in Portugal for the worlds.
Larry,
The other thing worth trying it find a setting that it will run at and just let it run for as long as you can. It might just need time. It might have gunk the pump or whatever. Also, lean the low end some, but it might just need run. The diaphram might be stiff and just needs sometime,
Arch
08-09-2009, 09:15 AM
#14
RE: OS 140RX Need Help
ORIGINAL: d_bodary
Well the stock OS# is 46030008
The CFI bearing # is 29430010 This is the one you want if at all possible. If you are using the unsealed one it will work just won't last any where near as long.
As far as changing the bearing it is the same as replacing any typical OS bearing.
The one big difference is the piston ring. it has to be lined up with the pin in the ring groove otherwise the ring will not compress enough to put the sleeve over the piston.
Leave the hammer in the toolbox. if you have it lined up correct the sleeve will smoothly go over it. It's a PIA but after two minutes you should have it.
As far as the needle valve go on Tower's website Look for the parts for the OS140RX and they show the two different needles. should be able to tell which one you have by the pictures.
One other thing the key for the prop washer only goes in one way the flat side to the engine.
Well the stock OS# is 46030008
The CFI bearing # is 29430010 This is the one you want if at all possible. If you are using the unsealed one it will work just won't last any where near as long.
As far as changing the bearing it is the same as replacing any typical OS bearing.
The one big difference is the piston ring. it has to be lined up with the pin in the ring groove otherwise the ring will not compress enough to put the sleeve over the piston.
Leave the hammer in the toolbox. if you have it lined up correct the sleeve will smoothly go over it. It's a PIA but after two minutes you should have it.
As far as the needle valve go on Tower's website Look for the parts for the OS140RX and they show the two different needles. should be able to tell which one you have by the pictures.
One other thing the key for the prop washer only goes in one way the flat side to the engine.
I have the stock needle….
My spare main bearing is a Boca Bearing…P/N 6904Z and it is either shielded or sealed…
There appears to be no detectable play in the main bearing currently installed in the motor…
My strategy is to flush the pump first and see how it responds…If no go, then replace the main bearing…
Thanks for all the help, I will keep you posted…Hopefully we will get a few practice flights in yet today…
Larry
Larry
08-09-2009, 11:35 AM
#15
RE: OS 140RX Need Help
Thanks Arch...I pushed some Denatured Alcohol through the pump and it seemed to clear that up quite a bit...If I let it sit it will drip a little now and not at all at idle. So that seems to be under control...
Now it idles very well and I can adjust top end. I'm getting about 7,900 on a 4 bladed prop 15.5x12 APC w/ PM Mean Green (15% w/ 18% all synthetic oil).
However, once it idles for any length of time or even 1/2 throttle, it will bog down and quite as soon as I start to advance the throttle. If I pinch the fuel tube it will pick up and run. If I go high then low and back to high throttle without too much delay it transitions well. If I'm at idle for about the same time as stall turn down line (2 or 3 seconds) it will bog down...
This is what I'm assuming everyone has keyed in on as the symptom of a main bearing going bad...
Off to surgery...now I get to see what the inside of a 140RX looks like...
Again, Thanks for all the help....
Now it idles very well and I can adjust top end. I'm getting about 7,900 on a 4 bladed prop 15.5x12 APC w/ PM Mean Green (15% w/ 18% all synthetic oil).
However, once it idles for any length of time or even 1/2 throttle, it will bog down and quite as soon as I start to advance the throttle. If I pinch the fuel tube it will pick up and run. If I go high then low and back to high throttle without too much delay it transitions well. If I'm at idle for about the same time as stall turn down line (2 or 3 seconds) it will bog down...
This is what I'm assuming everyone has keyed in on as the symptom of a main bearing going bad...
Off to surgery...now I get to see what the inside of a 140RX looks like...
Again, Thanks for all the help....
08-09-2009, 01:28 PM
#16
RE: OS 140RX Need Help
The bearings play a big part with the RX.
I have adjusted the pump on mine years ago. Ran much better, seriously helped the mid range madness that accompanied many a RX.
Mine was so rich is was spitting globs of fuel out of the card whist running in the mid range!
I read about the cure in Don Lowes RCM column a decade or so ago.
He'd received an article from Australia and published it in his column.
Worked great.
I have adjusted the pump on mine years ago. Ran much better, seriously helped the mid range madness that accompanied many a RX.
Mine was so rich is was spitting globs of fuel out of the card whist running in the mid range!
I read about the cure in Don Lowes RCM column a decade or so ago.
He'd received an article from Australia and published it in his column.
Worked great.
08-09-2009, 04:02 PM
#17
RE: OS 140RX Need Help
First I want to thank Jeff Hughes. He and Steve Maxwell were the two that helped me get started in pattern in 2003. Jeff spent about an hour total with me on the phone talking me through the main bearing replacement.
The engine is running strong. I replaced the front bearing, rear bearing, and piston ring (Dennis told me how to do it right) because I didn’t follow proper directions.
Idle’s reliably for over a minute at 2,000 RPM…No Hesitation transitioning to full throttle and no spitting fuel out of the carb at all…
I did not need to mess with the LE needle. So the solution to this was…
1) Purge the pump with denatured alcohol. I used about 5 ounces…
2) Replaced the main bearing…
Thanks a toon for everyone’s input…
Larry
PS…Hope to see ya at Quincy next weekend for those attending. You may want to bring hard hats while you judge my flights…vbg
08-09-2009, 08:17 PM
#18
RE: OS 140RX Need Help
Final update...
Got to the flying field and charged everything up…
Started the 140RX and tons of power running very smooth. Lisa took the Temptation out to the runway, one more run up to clear the engine…
Take off was beautiful, very smooth at ½ throttle and very nice climb out to about 20’ and bank to the left for a easy 180 degree turn down wind…
Leveled wings and was about 100’ and added power…No power, now a glider….it was a tight rope staying just above stall to land easy in the tall weeds…
I observed the tip stall about 2 feet above earth, and yep it’s a composite fuse…you know where it folded. That was the only damage…Repairable to some, not sure I want the task…
I have no idea why the engine quit and will probably never know at this point…
As for my weekend, this was the second plane in two days that were sacrificed to the RC Plane Gods if you will…Lisa’s trainer met it’s demise yesterday while my dad was on the buddy box. He got into trouble and I took back control at about 50’ with no problem. Well until I pulled elevator to gain altitude. I observed a narrow blue covering that I couldn’t place right before she headed to earth at full throttle. My thumbs were in the low left corner on the right stick and full up on the left stick. I held it in that position to verify what happened…
The blue line was the only blue on the plane…The leading edge of the wing. Normally not a bad observation if the plane is coming toward you, however, it was going away from me. The wing left the plane when I pulled elevator…The wing first lifted on the left appearing to bank sharp to the right…What I saw verified my final stick positions…
I’ve only lost one other plane since 85’…I guess we all pay up sometime or another…
Not sure what I will do from here, but we will not be making Quincy, OH…
Larry Diamond
