I am seriously considering going to the Lone Star Nats after being away from combat for awhile. (There currently is no combat flying in AZ)to fly SSC.
I got my stuff out and have been overhauling it.
I am having a problem with my 15 LA.
I followed the break-in procedures on the Battle Axe website.
Did everything recommended except the needle valve is mounted on the frame and not attached to the back plate.
The backplate has been sealed with RTV I am using 30% heli Fuel.
I am at 5280 feet in altitude.
I am only getting 16700 RPM. These are fairly new 15 LA engines with only about 6 flights on them. O.S. A3 plug. The muffler is stock as per the recommendations on the Battle Axe site.
Any suggestions as to how to get 17,500?
Al Tomlinson
Bisbee, AZ
15 LA Issues
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Alex Treneff
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<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Pathous</i>
<br />AL the high elevation you live at is causing your problem along with the engines still being new. Get as many runs on them as you can before you head to Texas. Also you will notice a good change in performance at the lower elevation.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">Scott is right on. Altitude will affect the performance of the engines. Some guys at close to 5,000' have said that they could hit 17,500 with the 30% by following the article. What weather conditions were you flying in?
Although 16,700 is plenty for club combat (we usually just use 15% fuel at our club fun-combat), if you follow the procedure listed, the LA will definately turn 17,500 at lower elevation (Texas).
Until you try the engine at lower elevation, don't drill out the baffle or stinger or anything. Guys make these mods and it really just complicates things.
<i>The engineers at OS designed the engine to run correctly as it is</i>. If they stinger needed to be larger, they would have made it larger!
You may need to make slight changes to get 17,500 at 5,300' but get a few more flights on the engine, and try it stock at low altitude before you make irreversible changes! Then go from there. [;)]
Hope to see you at the Lone Star Nats! [8D]
<br />AL the high elevation you live at is causing your problem along with the engines still being new. Get as many runs on them as you can before you head to Texas. Also you will notice a good change in performance at the lower elevation.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">Scott is right on. Altitude will affect the performance of the engines. Some guys at close to 5,000' have said that they could hit 17,500 with the 30% by following the article. What weather conditions were you flying in?
Although 16,700 is plenty for club combat (we usually just use 15% fuel at our club fun-combat), if you follow the procedure listed, the LA will definately turn 17,500 at lower elevation (Texas).
Until you try the engine at lower elevation, don't drill out the baffle or stinger or anything. Guys make these mods and it really just complicates things.
<i>The engineers at OS designed the engine to run correctly as it is</i>. If they stinger needed to be larger, they would have made it larger!
You may need to make slight changes to get 17,500 at 5,300' but get a few more flights on the engine, and try it stock at low altitude before you make irreversible changes! Then go from there. [;)]
Hope to see you at the Lone Star Nats! [8D]
Al,
There are a lot of ways to break in an engine. Most do not recommend breaking them in by flying them on a plane.
You want to control the heat cycles, and the only way to do this is by using engine test stand. Use a 7x3 prop (this will reduce the load and heat during break-in). Run the engine for no more them 1 minute with the barrel all the way open, but with needle set very rich. Do this 4 or 5 times, after each run let the engine cool all the way down to air temperature. Then do 4 or 5 runs at 5 minute run times, each time leaning the needle slightly, allowing the engine to turn more RPM. After completing these steps you are now ready to fly this engine.
I would not break an engine in with 30% nitro (too much heat), maybe 15% with at least 18% oil. I also, replace the plastic back plate with an aluminum back plate (the plastic back plate will eventually leak) and drill out the stinger on the muffler. I think, if you do this way, your engine will produce good power for a lot of years.
Some of my LA’s are 5 years old and have never been rebuilt.
Roid
There are a lot of ways to break in an engine. Most do not recommend breaking them in by flying them on a plane.
You want to control the heat cycles, and the only way to do this is by using engine test stand. Use a 7x3 prop (this will reduce the load and heat during break-in). Run the engine for no more them 1 minute with the barrel all the way open, but with needle set very rich. Do this 4 or 5 times, after each run let the engine cool all the way down to air temperature. Then do 4 or 5 runs at 5 minute run times, each time leaning the needle slightly, allowing the engine to turn more RPM. After completing these steps you are now ready to fly this engine.
I would not break an engine in with 30% nitro (too much heat), maybe 15% with at least 18% oil. I also, replace the plastic back plate with an aluminum back plate (the plastic back plate will eventually leak) and drill out the stinger on the muffler. I think, if you do this way, your engine will produce good power for a lot of years.
Some of my LA’s are 5 years old and have never been rebuilt.
Roid
I appreciate all the information.
I will get some more time on them before I doing anything "drastic".
I do have a spare stinger laying around from an engine that was crashed. I will "experiment" with the spare part. But other than that I will do nothing except get more time on the engines.
Alex......
The weather as clear and cool, about 45 degrees and 3:00 in the afternoon.. We had significant weather the night before (rain/snow).
On a side note......
My 25 FX screams with 30% heli fuel even at the altitude we are at here.
I don't understand the difference other than the 25 is a little bigger!
Al Tomlinson
Bisbee, AZ
I will get some more time on them before I doing anything "drastic".
I do have a spare stinger laying around from an engine that was crashed. I will "experiment" with the spare part. But other than that I will do nothing except get more time on the engines.
Alex......
The weather as clear and cool, about 45 degrees and 3:00 in the afternoon.. We had significant weather the night before (rain/snow).
On a side note......
My 25 FX screams with 30% heli fuel even at the altitude we are at here.
I don't understand the difference other than the 25 is a little bigger!
Al Tomlinson
Bisbee, AZ
Only 3-4 of us are flying combat in Southern AZ on an informal basis.
We were flying SSC but the engines were not quite cutting it on launch....especially if there was any type of wind. (we are over 5200ft AGL) We went to stock 25 FX and that took care of the launch issues.
We had a great time 2 weeks ago with just 3 of us. 4 rounds with 3 midairs. Go Devil survived Battle Axe died! I got cuts every round!
I have not heard from proppy in several months. he is residing in Glendale, AZ last I heard. (About 250 miles North if here.) I have not seen him in the forums either.
Palomar is about 8 hours from me according to my GPS. I would like to get out that way if you all had a 2 or even 3 day event.I would spend the night at your field like I did a couple of years ago with proppy in my Pop-up trailer.
Geting out there for just one day would be hard to justify gasoline wise.
If you have a week-end event let me know.
Al Tomlinson
Bisbee, AZ
We were flying SSC but the engines were not quite cutting it on launch....especially if there was any type of wind. (we are over 5200ft AGL) We went to stock 25 FX and that took care of the launch issues.
We had a great time 2 weeks ago with just 3 of us. 4 rounds with 3 midairs. Go Devil survived Battle Axe died! I got cuts every round!
I have not heard from proppy in several months. he is residing in Glendale, AZ last I heard. (About 250 miles North if here.) I have not seen him in the forums either.
Palomar is about 8 hours from me according to my GPS. I would like to get out that way if you all had a 2 or even 3 day event.I would spend the night at your field like I did a couple of years ago with proppy in my Pop-up trailer.
Geting out there for just one day would be hard to justify gasoline wise.
If you have a week-end event let me know.
Al Tomlinson
Bisbee, AZ
You got it Al!
With Palomar running SSC and Open B on Sunday, I have been kicking around the SouthWest Scale combat we flew in the past...you know..where you won with a Zero no less!
Well, I have been thinking of running a Scale event at Fallbrook, the day before the Palomar event. So, in a way, it is a two day event... Would that be enough to drag you out?
Either way, great to hear from you. Sure wish Proppy and his crew and Mic Williams and his crew would get into combat again..
With Palomar running SSC and Open B on Sunday, I have been kicking around the SouthWest Scale combat we flew in the past...you know..where you won with a Zero no less!
Well, I have been thinking of running a Scale event at Fallbrook, the day before the Palomar event. So, in a way, it is a two day event... Would that be enough to drag you out?
Either way, great to hear from you. Sure wish Proppy and his crew and Mic Williams and his crew would get into combat again..