91" SkyWing ARS 300 Assembly Thread

[AKNick]

After 15 flights:
The motor is still breaking in.
The canopy has a little play in it side to side. But not up and down whatsoever. I wished they used Kevlar or even fiberglass at these areas as it’s doesn’t wear like carbon does.
The magnetic fuel dot from NWRC has popped out 75% of the flights with the blue poly fuel tubing. Not like my spot on RC versions. Also that fuel tubing will pop off super easy after refueling and it’s a bear to get off for the first refueling. It has a step in it, no barbs. So I have switched to tygon there to see if the flexibility and softness will help... we shall see.

 

[AKNick]

After my questionable dead stick, I decided it was time to remove the cowl and just look over everything.

But first I tried tuning it because it has a little (like a hiccup) hesitation from idle slammed to WOT. I cannot seem to tune it out. It bugs me. I could get it worse though which bugs me more. Because it dies. So I threw in the towel and said heck with it, time to check under the hood.

First off those cool little exhaust lips I made are working beautifully, not a single spit of black residue inside the cowling.



Next is I took the plugs out. Dark and gewy after 15 flights or so (10-15min each = about 3-4 hours of run time)



Aircraft left:


Aircraft right:



Both plugs gap checked at 0.020”


The savox 1267 throttle servo has a few clicks in it as it rotates by hand. Seems great otherwise.

 

[AKNick]

After pondering why my engine deadsticked, having a little tuning troubles, I decided to clean the carb. Other than a little bit of junk in the screen , a little reside from a needle - it seemed fin to me. Slapped it back together and went back to basics. GP-76 screws are both set at 1.75 turns out. Reset and went to the field.

Ran ok, little bit of smoke in the exhaust, worked it's way up to WOT. Sounds Rich to me but ran pretty good. Used Terrys engine tuning guide and closed the LSN a bit, and found my little hesitation gremlin from before. gentle, but it was there. Opened up the HSN and it went away but the throttle response wasn't as good. Still not bad at all and much more reliable. so I said good enough for a flight.

Flew it three times, nothing but smiles and getting more and more comfortable with the plane, on the deck, tail tickling the ground. Awe yeah..... until my fourth flight. Mid throttle after flying IMAC for a bit, in a down wind gentle climb the motor died. Just like before. Once again Altitude was my friend. I was able to to a quarter pattern downwind turn to a perfect landing. A squirrel (non-flying type) may have abandoned tree at one point.... got close fellas. j/k!
As soon as I landed I ran the engine, not one single issue. This seems to happen to me a lot. Feeling a little defeated. Doubt it's overheating, not a low idle issue (also using a idle up switch), 8min into my flight, flying into breezy air from a glacier, so hmmmm. Fired up after four flips on the ground, and no issues through the run up, engine now has about 2 gallons though it and still emitting some black break-in goo from the pipes. I did notice when I took the canopy off it was warm inside which makes me wonder if I need to open up the cowling more or another panel in the fuselage for air to exit.
It's strange to me that it ran great for three flights and 8 min into the fourth when this happened again. I'm thinking it may just be getting a little too warm in the cowling. Plane sat for about 10-15 min before the last flight as well. Acts almost like I hit the kill switch - running perfect for almost 50 minutes today and the half way through a flight just dies. hmmmmmmm

I know this isn't an engine forum. but might open it up a bit more under the hood. Plane flies great. I do think it may be a little nose heavy still though.

Also switching to tygon for the fill line helped. The line stayed in the last four flights, and also grabs to the fitting better.

 

[Snoopy1]

From all your explanations I would be stumped as well. After 50 minutes this happens is strange. The only thing I can think off is the longer a plane is run the hotter things get that also depends on how long between flights. But normally if an engine is hot it is difficult to start but after 8 minutes is strange. If it were me I would just change the ignition if I had a spare they are heat sensitive. Sorry I know not much help.

 

[AKNick]

From all your explanations I would be stumped as well. After 50 minutes this happens is strange. The only thing I can think off is the longer a plane is run the hotter things get that also depends on how long between flights. But normally if an engine is hot it is difficult to start but after 8 minutes is strange. If it were me I would just change the ignition if I had a spare they are heat sensitive. Sorry I know not much help.

I’ll take any advice I can get. I’m with you on the ignition. Seeing that it’s happened after multiple flights, leads me to believe some sort of heat issue, but not carb related. Under the canopy was hot, there is a 2” hole for the carb is the only way hot air can enter. Ignition is on the motor box. Maybe my 3DPrinted ignition holder is not isolating the vibrations that well? Seems to me I need to open the cowl a bit. It’s not going to hurt it.

 

[Snoopy1]

Just a suggestion take it out of the holder put four small sponges at the corners to cool all around just try and add the hole and see if it helps.
Another thought can you fly without the cowl and see what happens.

 

[AKNick]

Just a suggestion take it out of the holder put four small sponges at the corners to cool all around just try and add the hole and see if it helps.
Another thought can you fly without the cowl and see what happens.

It's so random, I dont think I'd be able to notice a difference at all. My engine should be getting rich as it breaks in. So after 2 gallons of fuel it's starting to do this. hmmmmm Time to take stuff apart, check wires, ect. First time it died was a second flight back to back and one min into that second flight. This one was 8 min in and it sat for 10-15min after the last flight. I always do some cool down laps before I land. It's not hard to start, and has always ran great after the dead sticks immediately after. Now isn't that interesting.

 

[Snoopy1]

Hate to say it but I have been in this situation a number of times and logic does not apply at the moment. So I do what we call is grab the low hanging fruit first even if it does not make sense but just do it set out process of elimination. First mix up a new batch fuel, Then change the spark plugs easy to do, then I normally re build the complete feud tank and I mean everything, Rebuild the carburetor, at this point I am getting desperate and will either buy a new carburetor or ignition depending how the engine is acting.

 

[AKNick]

Hate to say it but I have been in this situation a number of times and logic does not apply at the moment. So I do what we call is grab the low hanging fruit first even if it does not make sense but just do it set out process of elimination. First mix up a new batch fuel, Then change the spark plugs easy to do, then I normally re build the complete feud tank and I mean everything, Rebuild the carburetor, at this point I am getting desperate and will either buy a new carburetor or ignition depending how the engine is acting.

Ive been flying the same fuel on another plane so cant be that. I can use the process of elimination by what I know. Hot under the canopy, engine runs great, Exh cut outs are the same as with other planes with this setup, fuel is OK, a little bit of fluff in the carb screen - but not alarming, Ignition never seems to skip a beat.
I've heard of people with Savox 1267 throttle servos get twitchy after heavy use and have heard of them causing random deadsticks..... Maybe I need to stress test the servo and open up the tunnel for some cooling air as under the canopy shouldn't be hot. Thats two steps that are free and plausible - may just start there.

 

[Das_Stig]

Hey Nick,

I’m running the same plane and motor as you, I’m even running your ignition mount. I haven’t had any noticeable heat issues in the cowl. My is engine well baffled. All the cut outs are open under the fuse with an RE3 in the tunnel.
Normal CHT has been under 200F in the air.

Thanks for keeping us posted! I'm very curious to see what you find especially since I'm running a similar setup!