acdii

oops. Servo failure my toocan.

raptureboy

After a crash like that how would you know it was a servo failure? The engine sounded poorly tuned also.

j301

My Feedback: (12)

It was obviously an electrical problem, didn't you see the way it "grounded out" there at the end? (And I got to say, that's some bad ju-ju posting that so close to me finishing up!)

As far as mine, guess I will just finish it up as a D, and I may have doomed it to a similar fate as I started adding details like painting the radio gear and adding gun barrels, etc.! I had to leave the carb stock and add a hinged door for the needles, I found the pitts muffler would sit over the top of them if I rotated the carb anyway. I also added an aluminum flange between the muffler and carb and put the air dams in the intake. I found I really had to carve up the cowl to clear the engine, but I guess that will help the cooling. I'll get some pics when I get a little closer. I think I might maiden it without decals, then if all works out I will hit up Callie for a different scheme. I've already painted the stripes on the bottom of the wing so I'm kind of committed to a different scheme anyway.

Quigleywins

After some thought I've gorn with the Keleo Exhaust as you have advised. I am also going with the 100.Saito . As soon as it arrives I will post some photos of the fit. Again thanks for the help.

RC-CAKES

My Feedback: (4)

Congrats! You will like the Keleo. Be sure to tighten the bolt well and safety wire it. Thats it. I posted a video link below. It is an early video of the plane with the exhaust on it. The engine has broken-in since - and sounds even better. Love the Saito sound. The videographer... well... not a pro. haha. Enjoy.

https://www.youtube.com/watch?v=db8LzAr5-xc

j301

My Feedback: (12)

Anyone have a line on where I can find documentation on where all the incidental "no step", "service port", "no push" type of markings are laid out?

Duplicator41

My Feedback: (1)

Here you go.




Cheers

j301

My Feedback: (12)

Awesome, thanks!

j301

My Feedback: (12)

So the maiden didn't happen. Got to the field and the engine wouldn't stay running (VVRC 20). I'm at the point to where I don't know what is wrong with it. I have re-plumbed the fuel system, checked it with a different ignition, I have even pulled the motor (twice) and bench ran it and re-tuned it (can get it to run great on the bench). To make a long story short, the last time I bench ran it (and got it to run great for a good amount of time), the only thing I did was move the engine itself to the airplane. The ignition was out of the plane, the tank was the one from the test stand, the battery was from the stand, literally the only difference was the engine was screwed to the same brand engine mount in the plane (no cowl) as I have on the test stand. I even ran the fuel line the same way it was on the stand.

I cleaned the screen in the carb, changed filters, I have a nipple threaded onto the center of the diaphragm cover plate (soldered shut the original hole) to run an air line to the fuse so positive pressure wont freeze the diaphragm, but it just wont run if it is any where near the fuse. Im beginning to think the motor is afraid to fly! (perhaps I can just use it as a fan!) I've tried tuning it rich, lean, and every combo with the high/low needles. The best it will do is run for about a minute (from cold), then die. It will re-start, but then die. If I am able to get the rpm's up enough it will die, then restart itself off the prop inertia, die,,,, for about three or four times, then die for good. I have to re-choke, then the process just starts over. (I even have a shop fan blowing on it so it doesn't overheat, just like I do on the stand). I've never had this issue before and its been driving me nuts since Saturday.

The only other thing I can think to do is add one of these so it will pull air from the fuse:

I have this issue posted over on a VVRC 20 page here that someone else started, so if you see it over there, sorry for the double dipping. Any thoughts or ideas would be a great help!

Aiden88

My Feedback: (5)

What is the difference between the engine on your test stand versus mounted on the airplane? Do you have the cowling on? How is your tank orientation on the airplane? Higher, lower or level within the carb? How is the tank orientated on your test stand?

It it seems the engine is fine but your installation on the airplane is flawed somewhere.

j301

My Feedback: (12)

In its last attempt the only difference was that it was bolted to an engine mount that was bolted to the airplane instead of bolted to an engine stand. On the stand, I have the tank strapped to an upright basically even with the carb. When I put just the engine in the plane I had the plane in a cradle I made that has vertical uprights above the saddle the fuse sits in. I fastened the tank from the engine stand to the side of the cradle at the same height. I also fastened the battery (with and without a switch) to the cradle as well as the ignition unit. The only thing different is the throttle servo is hooked up (using a plastic ball joint and nyrod) as opposed to the nyrod throttle linkage (to a "lawnmower" type throttle) on the stand. The cowl was off, but the initial run was of course with it on (at the field).
I agree there is something (or just plane bad mojo) with the installation, but the only thing left seems is airflow into the carb. Here are a couple pics of the set up, and this version was just the last of many tries, with the various parts in and out of the plane, tunings, etc.

acdii

Well dont feel bad, at least your plane is still in 1 piece and not 3. I had 2 good flights on it, and today went to make my third, and it was a great flight, up until landing. Wind was out of the north and was pushing the plane south when lining up to land, and for some reason rudder had no effect on yaw, usually I can crab a plane right in when its a crosswind like today, but no rudder at all when landing, and it seems like there is not much at high speeds either, I can usually roll the plane with just rudder.

Anyhow, on my second approach it was good, but too high so I aborted and went around, this time it drifted too far south and I was afraid it might hit a tree, so I throttled up, which retracts the flaps, and I must have gave it too much up elevator, it snapped over and did a beautiful loop, right into the ground. If I had 2 more feet of altitude it would have cleared with maybe taking out a few leaves from the soy beans. Just a dumb mistake on my part, I should have just rolled left on power up instead of trying to climb out. Anyway, the fuse snapped in half right at the instrument panel, and the gear got ripped out. Damaged a few servos in the wing too including the throttle servo, going to need some new gears.

It dove into the ground with full up elevator. The only thing I may not be able to fix is the cowl and spinner. Spinner got bent and I may not be able to straighten it out. The rest I can repair easy enough, and just recover it.

raptureboy

Oh mannnn, that just sucks big time. So sorry to hear this, but glad you are going to rebuild it. Maybe start a rebuild thread to show us. J301 I think you have a bad ignition, have you called VVRC yet? Where are yoou mounting the ignition on the test stand vs the plane? I just had a bad ignition on mine a while back and it made me crazy thinking it was a tuning issue. It would misfire about every 15 revolutions and I sent it back to Tower and they sent me a new one. Hook up the ignition and pull the plug and rotate it by hand to see how it sparks.

crazystick

My Feedback: (1)

j301 , Check your vent line , it may be party kinked !



cfrazystick

j301

My Feedback: (12)

I haven't been doing a very good job of describing the set up of the motor between the stand and plane so, as they say, a picture is worth a thousand words.
I realize that there are only two screws, the cap on the plug isn't tight, etc, but what I did here was just to "layout" the components as they were in the various runs. This shows where they were, roughly as they got moved around to see if it had an effect, at the time of the last try. Prior to this I tried two different ignition units, all new plumbing, different batteries, switches/no switches, cleaning the carb, different filters, etc, all both while the motor was being fed from the plane and the stand.
Here is what it was like on the stand when it ran fine:


And here is what I mean about the "only thing different is the same brand motor mount its screwed to:"


As you can see, the fuel tank and line is the same, the ignition is out of the plane (and moved around a few times), the battery isn't the one from the plane, etc. And this is after trying everything from the plane while the ignition was in it and its own fuel source, before and after re plumbing.

On the stand I am using a nyrod to control the throttle, in the plane I am using nyrod to a servo, but I did re-install the idle screw to keep the idle the same from stand to plane. Both have plastic ends that attach to the throttle linkage.

This really has me scratching my head, the stuff on the stand is what I have used to run every motor I own successfully, even this one. Proximity to the plane is the only thing left. It has to be something with air flow, though it did this both with and without the aluminum shield I made to separate the carb. and the stand has roughly the same hole behind the carb as the plane's firewall does.

SkyPilot101

Have you tried a new plug? Is your plug cap all the way on? And I mean ALL the way on, down to allmost touching the head. I doubt that you have a air feed problem. And what do you mean, "Aluminum shield to seperate the carb" Since you hade the carb off, dos it visably draw fuel when you briskly rock the prop back and forth against compression? You should see the fuel jump forward to the carb when you rock the prop

j301

My Feedback: (12)

I'll try to answer these in order; no new plug as it ran on the bench, cap double checked every time, aluminum heat shield is basically the same as the other guys ran on theirs a few pages back-nothing to do with the carb, just an "air dam," the carb does draw fuel.

So now, I have re-routed everything away from the carb/hole in the fire wall, and I re-routed the pick-up lead, it may or may not have been "pinching" but it was close to the motor so I moved it. Re did the breather/pump line so it doesn't flow past the carb intake anymore either.
First try: kept quitting, but I noticed the LED from the rcexl kill sw. was blinking every 20 or so seconds. (I was not using the kill switch during any of the previous tests, just now hooked back up). So I ran a standard switch to a different battery and unplugged the opto switch from the receiver. Now with some tuning it seems like it wants to run. It still has some odd traits around idle, but its not quitting. I don't know which thing fixed it, but I think it might be OK.
What I need to do now is figure out why the rcexl is killing the ignition? Is there some way to re-set it? It might have happened when I was running the motor with an external battery and switch and the radio was powering the opto switch while it was not hooked up to the ignition. I tried to keep its switch off, but was paying a bunch of attention to it.

acdii

I had this same issue with mine in the 4*. I believe it was due to a loose wire in the harness. Once I got everything strapped down tight it worked fine. Triple check all those connectors on the Opto Kill, I found one that had the label on backwards and did not work properly. Once I figured that out it worked fine.

acdii

Any thoughts on lack of rudder authority while landing? Should I be able to crab it into the wind with flaps down and full left rudder when the wind is hitting it from the left, or just deal with the plane being pushed sideways? I would expect there to be more rudder than it had.

j301

My Feedback: (12)

From my experience, a 'brisk to stiff' cross wind will overpower the rudder causing it to 'weather-vane' when using flaps. Usually have to land at half or no flap and a little hot.

acdii

Mine was just sliding south, nose pointing straight ahead, no indication at all of trying to turn into the wind, I would have expected to at least see a little yaw with full rudder. One other thing I notice is on taking off it pulls left and rudder doesn't seem to help much, but that could be the toe on the gear. I will revisit that setting when I repair the mounts.

j301

My Feedback: (12)

Someone had mentioned earlier that the geometry of the flaps is a bit off due to horn placement. If one flap is lower then the other by a little bit, then what could be happening is a cross-control skid just like you would have if you used right ail/left rudder. And you might be right about the toe in/out. Ground and air handling could be two different issues that look the same.

raptureboy

J301, check the end points on your transmitter for the switch you are using to control the kill switch. They need to be at full 150% at each position. I had the same problem with one I had and it liked to drove me crazy until I noticed the light blinking on and off. If that does not work it may be a bad kill switch as I had one of those also.

j301

My Feedback: (12)

Thanks, I tried that too, I think I just fried the thing not having it hooked up to the ignition but still to the receiver. Either that or it just went bad. I switched it out and took the plane out yesterday but I wasn't too confident in the gear, the struts kept working themselves loose so I didn't fly. I punted and hit it with some JB weld, one time fix I know, but I got to try something! So tomorrow I am taking it out again. I'll Let you know how it goes.

j301

My Feedback: (12)

So today was the maiden. I took out a Yak 54 with a G20 just to "work out the jitters." Take off roll was a bit tricky, way too touchy on the rudder. I later found that the expo I had dialed in somehow went away, took care of that real quick. The engine ran fine with a Xoar 17/6, plenty of power but I can see a 16/8 would provide more speed when I want it. 2 clicks of down trim is all it needed, the rest was neutral. I did notice a tad bit of left roll with flaps, but not enough to sweat it, I'll just fly with the sticks to fix it.
I have to admit, I was almost sure this one would come home either missing some covering, or in a bag, and I was nervous to take off after some taxi testing. I had the TF P 47, it flew ok, but me and it just "never got along" so I sold it and I assumed that the mustang would be harder or less forgiving then the P47 as that is usually the more stable of the two airframes. I have to say, this plane just "flew like it was supposed to." It grooves nicely, wasn't twitch or choppy and went where it was pointed. It actually flew better then the Yak I took to warm up with!
So I only did a hand full of circuits, brought the flaps to half, noticed the roll, did some more then brought down the gear (that are now stable thanks to the JB weld) did another circuit noticing nothing. Finally brought the flaps to full, still nothing out of the ordinary. Flew around at 1/4 and 1/2 throttle, no sign of stall or instability. Then I figured I had better start finding out how this thing was going to land. Expecting a bunch of go-arounds, I lined it up, still with flaps at full, and let it "sink" at about a 40 to 45 degree with slight nose down. Got over the threshold and chopped power, flared, and watched it tippy-toe down the runway on its mains with only 3 slight hops (not hard, just the flaps wanting the wing to stay up-, less then an inch high I would say). It never wanted to nose over, which I was afraid of even though I fly off pavement, kept rolling strait down the center so I let off the down (to fix the hop) and let the tail drop when it wanted to. Turned around and taxied in in an almost state of disbelief of just how well the entire thing went. So its "earned its stripes" I'd say, which means I will be putting on those decals now. I was thinking I would order some from Cali, but now I might just have to through on the ones it came with 'cause I don't think I can wait!