Airplane help

[4u2nv]

I have a Great Plains Pt20 airplane that when i got it, it had a O.S. .15 engine which made it hard to fly and needed too much runway. So I put a new O.S. .25 motor in it (The plane can fit up to a .29) and after I hooked everything up it started up fine. Then I started to do the break in and ran 1 full tank through until it ran out and the plain died. After that I have been unable to start it at all. The exhast is spitting out this really milky looking goo. Any suggestions? I'm guessing its running wayy to lean and wondering where is a good place to adjust the wheel to get it going? Please help me out. Thanks~Andy

 

[scottm]

I never heard of that. Is the fuel fresh? It sounds like it has water in it. Alcohol absorbs water. Check the glow plug, make sure your battery is heating it properly. Check the compression. If everything is good, it should start.

 

[Error401]

Exactly what proceedure did you follow during break in?
Scott was right about water in the fuel.
You did put fuel in it, and not something else like windshield washer fluid (yes it has happened).
Check the plug.
Don't screw with the needles till you get it to fire again
what did you do to it after it quit after the first tank?
What fuel are you using.

The milky fluid kind of bothers me. I have not seen this happen to an airplane engine, and I've flown alot of planes. When oil is mixed with water, it'll make that kind of substance.

 

[4u2nv]

I'm using "Sig" champioship fuel 15% Nitro. I've had the fuel for maybe 2 months, and it has been sealed in its original bottle, in my home. The glow plug seems look normal and heats up fine. For brake in I was instructed to have the plane restricted so it can't move and then let it run on 3/4 throttle and let 3-4 tanks run through it. I kinda had some problems starting it because when the engine came out of the box the screw was screwed all the way in. So I did the suggested 1 and a half turns and eventually it fired up, after a few minutes of trying (Electric starter). Then after the 1st tank went threw it, it died. I filled it back up again, and I couldnt get it to fire. The 1st time I started it, i noticed the milky goo on my wing, but I thought maybe it was oil in the cylinder for storage on the motor before it sold. But now it wont start, and the milky stuff still shoots out every once in a while, and that kind of worried me too. I will get to mess with it some more tomorrow if weather permits. But if anyone has any suggestions, Id GREATLY appriciate it. Thanks for the help so far! ~Andy

 

[scottm]

That sounds like a risky way to break it in. I always adjust an engine so I know it is too rich, then lean it from there. It is possible it ran too lean and caused some damage. You should evaluate its comression next. You should feel resistance to turning the prop by hand, kind of "springy". If you can spin the prop easily with your finger it may be toast.

Check the OS engines website FAQ page for more info:

http://www.osengines.com/faq/product-faq.html

 

[4u2nv]

I checked the compression and its good. What would u suggest for break in? I had 2 hobby shops tell me to do it like this. Thanks~Andy

 

[scottm]

Go to the OS website and follow thier recommendations for your type of engine, ringed or non ringed. Ringed engines should be run rich at part throttle for 3-4 tanks. Non ringed engines need to reach a certain minimum temp. Read this:

https://www.rcnitrotalk.com/forum/showthread.php?s=&threadid=14996

 

[4u2nv]

I got it going today!!!! I took out the glow plug, turned it over a few times and put in a new glow plug (3rd one since new motor)(Running 2 times!). I turned the screw all the way in, then out 1 full revolution. It fired right up! It was still running rich so I leaned it out and took er' for a rip.

All was going well until I had problems with a wind current and totally lost control. It ended up doing a nose dive at nearky 3/4 throttle ( I was trying to fly out of it) right into a plowed field. (Here in Mn the snow has just melted like 2 weeks ago, which made it VERY sloppy!!!) It broke the motor mounts, prop, nosecone, the backplate with the idel screw broke off, and a front crossmember. Was a mess. Shouldnt be to long to get her up and running again though. Thanks for all the tips to get it runnin'!!

 

[scottm]

Oh that sucks! Well at least you got it running. Planes are hard to learn, luckily I started out with an Aerobird, that is nearly indestructable.

 

[4u2nv]

Originally posted by scottm
Oh that sucks! Well at least you got it running. Planes are hard to learn, luckily I started out with an Aerobird, that is nearly indestructable.

That electric?

 

[scottm]

Yes its electric. It has the motor/prop in the back and a big tough plastic nose for crashing into stuff. I hit power lines, trees, a saghuaro cactus, a ford truck, etc. It lasted for a year of that.

 

[4u2nv]

cool, Can them do loops and rolls and stuff? I have been looking for one on ebay, a firehawk or a bird and they never say if they do rolls or loops.

 

[scottm]

There are several from the same comapny. The Firebird is 2 channel and can't do anythiung. The aerobird is 3 channel and can do loops but not rolls. You need alerons and 4 channels to do rolls. The aerobird is pretty fun and teaches you normal controls, unlike the firebird.