Problem getting out power from webra 1.20
04-09-2006 | 11:28 AM
#1
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From: Bogota, COLOMBIA
Problem getting out power from webra 1.20
Hi all
I have two webra 1.20 speed, running with same fuel, glow plug, pump, tank, etc
I am very happy with one I can run a 17x6 with no problem but with the other one I have not able to run even 15x8.
For the one I have problems with I have set the idle properly , when tunning the needle at full throttle it feels like is never reaching the highest rpm possible.
Once I start closing needle to increase RPM there's a point when it feels the engine too lean and then I have to reopen the needle but I never get the felling it's runnig at highest RPM, you know what I mean.
I am running a 15x6, but as said above with the other engine I run 17x6 with no problems.
I inspected the engine i have problems with and noticed the piston ring (in the top) was "welded" to the piston, (maybe the person who broke-in this engine did not do it properly and overheated), I loosened it, remove the carbon in the top of the piston, and now I measure the compression for both engines and the one with less lower power gives more compression with the one I am fine with.
Now I am lost, I was thinking about replacing the whole cylinder-piston-ring set for the engine but I am not sure it's gonna help me.(since compression is fine).
I am not very wise on webra engines, I know the compression I read has nothing to do with the one when the engines is warm, but anyway I want to know what to do.
I would really appreciate any help you guys can provide me with, it's ons of the first time I feel lost and not knowing what to do.
Regards
Omar
I have two webra 1.20 speed, running with same fuel, glow plug, pump, tank, etc
I am very happy with one I can run a 17x6 with no problem but with the other one I have not able to run even 15x8.
For the one I have problems with I have set the idle properly , when tunning the needle at full throttle it feels like is never reaching the highest rpm possible.
Once I start closing needle to increase RPM there's a point when it feels the engine too lean and then I have to reopen the needle but I never get the felling it's runnig at highest RPM, you know what I mean.
I am running a 15x6, but as said above with the other engine I run 17x6 with no problems.
I inspected the engine i have problems with and noticed the piston ring (in the top) was "welded" to the piston, (maybe the person who broke-in this engine did not do it properly and overheated), I loosened it, remove the carbon in the top of the piston, and now I measure the compression for both engines and the one with less lower power gives more compression with the one I am fine with.
Now I am lost, I was thinking about replacing the whole cylinder-piston-ring set for the engine but I am not sure it's gonna help me.(since compression is fine).
I am not very wise on webra engines, I know the compression I read has nothing to do with the one when the engines is warm, but anyway I want to know what to do.
I would really appreciate any help you guys can provide me with, it's ons of the first time I feel lost and not knowing what to do.
Regards
Omar
04-09-2006 | 11:32 AM
#2
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RE: Problem getting out power from webra 1.20
ORIGINAL: niche
Hi all
I have two webra 1.20 speed, running with same fuel, glow plug, pump, tank, etc
I am very happy with one I can run a 17x6 with no problem but with the other one I have not able to run even 15x8.
For the one I have problems with I have set the idle properly , when tunning the needle at full throttle it feels like is never reaching the highest rpm possible.
Once I start closing needle to increase RPM there's a point when it feels the engine too lean and then I have to reopen the needle but I never get the felling it's runnig at highest RPM, you know what I mean.
I am running a 15x6, but as said above with the other engine I run 17x6 with no problems.
I inspected the engine i have problems with and noticed the piston ring (in the top) was "welded" to the piston, (maybe the person who broke-in this engine did not do it properly and overheated), I loosened it, remove the carbon in the top of the piston, and now I measure the compression for both engines and the one with less lower power gives more compression with the one I am fine with.
Now I am lost, I was thinking about replacing the whole cylinder-piston-ring set for the engine but I am not sure it's gonna help me.(since compression is fine).
I am not very wise on webra engines, I know the compression I read has nothing to do with the one when the engines is warm, but anyway I want to know what to do.
I would really appreciate any help you guys can provide me with, it's ons of the first time I feel lost and not knowing what to do.
Regards
Omar
Hi all
I have two webra 1.20 speed, running with same fuel, glow plug, pump, tank, etc
I am very happy with one I can run a 17x6 with no problem but with the other one I have not able to run even 15x8.
For the one I have problems with I have set the idle properly , when tunning the needle at full throttle it feels like is never reaching the highest rpm possible.
Once I start closing needle to increase RPM there's a point when it feels the engine too lean and then I have to reopen the needle but I never get the felling it's runnig at highest RPM, you know what I mean.
I am running a 15x6, but as said above with the other engine I run 17x6 with no problems.
I inspected the engine i have problems with and noticed the piston ring (in the top) was "welded" to the piston, (maybe the person who broke-in this engine did not do it properly and overheated), I loosened it, remove the carbon in the top of the piston, and now I measure the compression for both engines and the one with less lower power gives more compression with the one I am fine with.
Now I am lost, I was thinking about replacing the whole cylinder-piston-ring set for the engine but I am not sure it's gonna help me.(since compression is fine).
I am not very wise on webra engines, I know the compression I read has nothing to do with the one when the engines is warm, but anyway I want to know what to do.
I would really appreciate any help you guys can provide me with, it's ons of the first time I feel lost and not knowing what to do.
Regards
Omar
---------------
It sounds as though someone disassembled the engine previously and reassembled it with the cylinder sleeve turned 180 degrees. Look into the exhaust port and see if the sleeve's ports are aligned with the crankcase's exhaust port. Having the sleeve 180 degrees out will cause greatly reduced power, even with great compression.
04-09-2006 | 12:45 PM
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From: Bogota, COLOMBIA
RE: Problem getting out power from webra 1.20
Hi Ed
It sounds like you know a lot about engines
After quite a while I was ble to understand what you meant by your suggestion of checking whther the cylinder sleeve's ports were alligned with the ones of the crankcase.
I dismounted the muffler and saw a couple of rectangles with a space in between which I think it's the right thing to be sawn here.
I am attaching the picture I took and the exploded list webra posted for this engine(see link below) they look like they are ok
http://www.webraengines.com/motor.ph...e=AERO&lang=EN
Hope I am in the right path
Appreciate anehy help from all around to find out what's wrong with my engine
Regards and thanks again
Omar
It sounds like you know a lot about engines
After quite a while I was ble to understand what you meant by your suggestion of checking whther the cylinder sleeve's ports were alligned with the ones of the crankcase.
I dismounted the muffler and saw a couple of rectangles with a space in between which I think it's the right thing to be sawn here.
I am attaching the picture I took and the exploded list webra posted for this engine(see link below) they look like they are ok
http://www.webraengines.com/motor.ph...e=AERO&lang=EN
Hope I am in the right path
Appreciate anehy help from all around to find out what's wrong with my engine
Regards and thanks again
Omar
04-09-2006 | 11:30 PM
#4
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My Feedback: (14)
RE: Problem getting out power from webra 1.20
ORIGINAL: niche
Hi Ed
It sounds like you know a lot about engines
After quite a while I was ble to understand what you meant by your suggestion of checking whther the cylinder sleeve's ports were alligned with the ones of the crankcase.
I dismounted the muffler and saw a couple of rectangles with a space in between which I think it's the right thing to be sawn here.
I am attaching the picture I took and the exploded list webra posted for this engine(see link below) they look like they are ok
http://www.webraengines.com/motor.ph...e=AERO&lang=EN
Hope I am in the right path
Appreciate anehy help from all around to find out what's wrong with my engine
Regards and thanks again
Omar
Hi Ed
It sounds like you know a lot about engines
After quite a while I was ble to understand what you meant by your suggestion of checking whther the cylinder sleeve's ports were alligned with the ones of the crankcase.
I dismounted the muffler and saw a couple of rectangles with a space in between which I think it's the right thing to be sawn here.
I am attaching the picture I took and the exploded list webra posted for this engine(see link below) they look like they are ok
http://www.webraengines.com/motor.ph...e=AERO&lang=EN
Hope I am in the right path
Appreciate anehy help from all around to find out what's wrong with my engine
Regards and thanks again
Omar
-------------------
I don't have a Webra 1.20 with which to rotate the cylinder sleeve and make a comparison, but in your picture that does look real good (correct).
I'm scratching my head trying to figure out what else could be wrong.
04-10-2006 | 11:35 AM
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RE: Problem getting out power from webra 1.20
ORIGINAL: torque wrench
That engine appears to have been run very lean and hot, stuck ring?
That engine appears to have been run very lean and hot, stuck ring?
------------------
Were it my engine, it would be heading for the antifreeze filled hot tub for a clean up.
He did say that it had better compression than the engine that outpowers this one. Strange.
04-10-2006 | 01:02 PM
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From: Bogota, COLOMBIA
RE: Problem getting out power from webra 1.20
Thanks for the concern
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
04-10-2006 | 02:58 PM
#8
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My Feedback: (14)
RE: Problem getting out power from webra 1.20
ORIGINAL: niche
Thanks for the concern
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
Thanks for the concern
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
--------------------
If the cylinder sleeve isn't obviously damaged, I wouldn't replace the sleeve. That is the beauty of ringed engines. Most times, all you need is a new piston ring.
With ABC engines you need to replace both the sleeve (liner) and piston as a unit. Not so with ringed engines, unless there is obvious damage that you can feel with your finger.
04-10-2006 | 05:00 PM
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From: STOCKHOLM Akersberga, SWEDEN
RE: Problem getting out power from webra 1.20
ORIGINAL: niche
Thanks for the concern
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
Thanks for the concern
Actually it had stuck ring and I loosened it
I ignore for how long was the ring stuck but I am thinking it yielded an uneven wear in cylinder sleeve.
I am thinking about getting a new cylinder/piston/piston ring assembly
Do you thinks it's woth it to replace them?
Regards
Omar
I see from the pictures your engine is running a fuel with a high amount of castor oil which is good, but if it was stuck once it will stuck again soon. A good thing you can do is to gently remove the piston ring and make it smaller about 0,1mm, 0,004"inches, on a abrasive paper 200 grit. Put it back as it was before and you are done. I have done this several times on my big supertigres with great result and the ring did not stuck again.
04-11-2006 | 11:37 AM
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From: Bogota, COLOMBIA
RE: Problem getting out power from webra 1.20
Thanks everybody for the help
Last night I disasemble the other webra 1.20 I have and the cylinder exhaust ports look exactly the same.
I also will take other recommendations and what I am gonna do is to buy the cylinder sleeve and piston ring.
Since I hope the power will improve I'll switch to a 3 blade propeler.
Which one do you think will be the 3-blade equivalent for a 17x6 or 16x6 2-blade one?
As for the oil I use half castor half synthetic, but I guess it's been quite a long time since the engine was cleaned out
Regards
Omar
Last night I disasemble the other webra 1.20 I have and the cylinder exhaust ports look exactly the same.
I also will take other recommendations and what I am gonna do is to buy the cylinder sleeve and piston ring.
Since I hope the power will improve I'll switch to a 3 blade propeler.
Which one do you think will be the 3-blade equivalent for a 17x6 or 16x6 2-blade one?
As for the oil I use half castor half synthetic, but I guess it's been quite a long time since the engine was cleaned out
Regards
Omar
04-11-2006 | 12:05 PM
#11
RE: Problem getting out power from webra 1.20
Since the ring was stuck, the rings will have to seat again before power is restored. I would use a fuel with some castor oil till seated, then use a gallon of synthetic to clean it up a bit, then back to synthetic / castor mix.
