mtntopgeo

My Feedback: (12)

This was my first attempt at trying anything smaller than a .074. Frankly, I didn't think that little engine could drag even this 13 & 3/4 OZ model thru the air. What a pleasant surprise! Since thise was my first flight in several months, and THE first flight for this engine, & plane, I stayed conservative with 15% nitro, & a 6x3 prop. Considering my "rusty thumbs" this combo was more than enough for me. Good climbs, big loops, & nice rolls (all when I didn't screw up too badly.) Glides in a little fast, but I've got an extra servo on the wing for flaps. Gonna take me awhile to see if I can get that set-up working right. Also, pretty quick. Can't imagine what this thing would be like with a.074, on 30%, running at full song. Now, for the bad news; I haven't been able to run more than a half tank of fuel before the engine leans out & quits running. I use muffler pressure (Are these mufflers supposed to have a gasket?) Started with all new fuel line, & replaced the clunk line. Since the same set up works OK on the bench/test stand, I'm guessing that the fuel tank location is the problem. The tank (2 OZ round) is completely below the nva. Past attempts at using crank-case pressure with a carb tells me that I'd like not to have to go this route. Anybody else using this engine/plane combo? Any suggestions? ........................ George K

burtcs

mtntopgeo:

In the Last few weeks I've broken in five 061 Big Migs (15%, 6-3 APC) with about 4 onces of fuel. They're ready for the air IMHO. There were no muffler gaskets on any of them. The wire clip just barely holds the muffler tight.

regards - Steve B.

Jburry

Beautiful little engines, aren't they?

Sounds like your problem is likely the fuel tank location. Optimum is to have the centerline inline with the needle valve, and the tank should be as close as possible to the engine. Not a huge amount of draw available in these engines.

J

mtntopgeo

My Feedback: (12)

Steve, You're right about the wire thingy just barely holding the muffler in place. During a run, I can see the muffler shifting around, with the castor , & bubbles, flowing out from between the muffler, & the engine.

Jburry, I'm 90% sure that you're correct (about the fuel tank location). Unfortunately. I don't have too much choice, with the small fuel tank compartment. The outside, top of the fuel tank is about 1/4" below the nva. Options appear to be limited. (1), go electric.... ARRRRRGH. ...... (2) duct-tape the tank to the top of the fuselage... crude, even by my standards. ...... (3) use crankcase pressure, & fly WFO thru the whole flight. .... Before going any of these routes though, I'm in the process of glueing (Ultra Copper) the muffler to the engine. That goofy wire set-up hardly pretends to seal the exhaust. Since that muffler reduces the RPMs (with a 6x3 prop) by 1600 RPMs, I'm thinking that there should be some measureable back pressure there. Second, I've drilled a larger hole in the fire wall, & have installed a larger diameter fuel line. Can hardly blow thru the stuff that I originally tried. Hope to see what the results are, tomorrow. ...................... George K.

Jburry

Hey!

You can bend teh spring clip a tiny bit to keep the muffler tighter. A touch of RTV carefully applied does wonders for the seal. I apply it in the little hollow around the muffler opening, using a knife to scrape it down to a flat line between the top and bottom edges of the recess. Let this cure a night or 2. Then assemble the muffler to the engine, trying hard to keep it still while you do so, so as to not kill the seal you just made. Does work pretty well.

Is mounting your engine on it's side an option for you? This lowers the carb by about 3/4", and may just make the diff.

Good luck,

J

mtntopgeo

My Feedback: (12)

Jburry, I had given some thought about laying the engine on it's side, but either the muffler, or the nv is gonna hang below the plane. Before doing anything else, thought that I'd better try the present tankl, & tubing one more time; this time elevated. Removed the hatch & tank, CA'd some balsa in the tank compartment for a temporary shelf to lift the tank to the approximate correct level, replaced the tank, & held it down with several rubber bands. Then a trip to the flying field (cow pasture). .....Total success!!!! I had been using up about 42% of the tank capacity, before the engine would go lean & quit. Now, only a few drops left. Played until well after sundown. Not too wise for an old man with bad eyes, but was having too much fun to quit. ... Plan to install the Hayes 2ox retanguler tank. It'll fit in, on edge, without too much triming, & when I get it to the right height, just have to make a little turtle deck hatch. ................. Thanks for your input. .........................George K.

burtcs

mtntopgeo:

So how does it fly? I've got one of these I never finished that could be liberated from it's Speed 400 motor. Is there enough wing area? How about the control throws. Might be a fun way to put a sure-start or tee dee to work.

TIA - Steve B.

mtntopgeo

My Feedback: (12)

Steve, before giving a report on how this thing flies, need to report on my capabilities, first. Got into this hobby way too late in the game. Eyes already going bad, & reflexes near gone. After 3 years, I'd rate myself somewhere in the beginner/novice area, as far as flying skills are concerned. My "dirt nap" vs. clean flight ratio is probably worse than anyone else on this forum. In fact, I've pretty much stayed with only two different planes, mini super sportster (got 4 of them with various mods, & power-plants) & the Lazy Tiger (2 of them) because they "make me look good". With that in mind you might want to take my "report" with a grain of salt. ................... Set the plane up pretty much per instructions/plans, except I added another servo so that I could have flaps. I had a tad too much aileron than what the plans called for, & that nearly bit me during the first few seconds of the first flight. I barely just thought "aileron" input, & the plane was inverted. Immediately switched to low rates, & once the flight was over set it up per instructions, & then with a fair amt of expo. .......When I finally found the right prop for my profile (modified) mini super sportster, & "discovered" how to get the Norvel .074 up "on step" (set a tad rich, take up high, then put in steep dive) the thing turned into a beast as far as speed is concerned; but even then, with much, MUCH, more speed than the Simple, flying it is a walk in the park, & kind of "ho-hum" compared to the simple 400. Had the "simple" out again this morning. (still with the old tank held on with rubber bands). Had a ball! This thing is lite (mine is kind of porky, but still the litest plane that I've had in the air), turns on a dime, small, & gets outa sight in a hurry. Don't think that I had the adrenalin flowing this well since 30 years ago, during the days of sprint cars, & turbocharged street bikes. Does not float in like the MSS, but with the flaps, I'm not having too much trouble setting it down pretty close to me, regardless where the plane is when the engine stops. This is one of the few plane that I've bought which I'd get another if (when ) I crashed it. Just wish that my flying skills were up to taking this thing up with a 5x4 prop with 35% nitro, & no muffler. Ace says that this plane will handle the .074. What a hoot that would be!!!!!!! .................. Well, rambled on long enough & probably bored everyone half to death. Good luck with your "400" ................ George K.

rrragmanliam

My Feedback: (1)

Mtntopgeo,

I doubt the tank location is a problem. I've flown one of these with the same setupf for a very long time without the problem your having. It sounds to me like you have a hole in the fuel line INSIDE the tank. Even a pinhole in this line will cause the problem your describing. Disassemble the tank and replace the line, also debur the fuel line nipple so you dont put a hole in the line when you assemble it.

Darren

mtntopgeo

My Feedback: (12)

Darren, got to admit, that, even though the tank is mounted low, I thought that (with muffler pressure) the engine would draw the fuel. As I stated earlier, started with new fuel line (was an old tank). Then with the problem, I replaced it again. Also, the clunk is not hanging up. I even pressure checked the last fuel line(s) with a syringe & hemostat and soap water. All looked well. One noteworthy item; on each flight with the old fuel tank location, the engine stopped with exactly 42% of the fuel used. Admittedly, I may have "fixed" this problem by overpowering it, not by finding & correcting the cause. However I'm fresh out of ideas. Thanks for your input. ............................ By the way, could you tell me what you're using for prop & fuel. If I ever get my flying skills up, thinking of a 5x4, with 35% . In the ballpark? ........................ George K.

rrragmanliam

My Feedback: (1)

Hello George,

In the pics the prop is a cox 6x3. It's actualy a little too much prop in my opinion. My favorite prop for the Norvel .061 is the APC 5.7X3. I use 30% heli fuel in my 1/2A engines. Your 1/2 tank issue has me perplexed. If it were me I'd completly disassemble, clean, inspect and reassemble the engine and fuel system. I just dont see tank location as a major issue in this aplication. There have been times when I've had the same problem and found somthing I missed earlier, I'm still suspecting the fuel system.

Darren

SGC

best prop I found was a MAS6x3.5 cut down to 5.5"

digital_trucker

Another possibility is a Graupner 6x3, when I measured them they actually came in closer to 5.75 - my Wasp turns good on it.

rrragmanliam

My Feedback: (1)

SGC, DT,

I'll have to try those prop selections sometime (as long an My Norvels are running)! I think what what we are all saying here is a diameter of less than six (6), and a pitch of less than four (4) is the way to go to make this engine run in it's "Happy Zone"

Darren

Jburry

Another good option is the APC 6x2, if you want more thrust and less speed. Should 3d that plane nicely. You'll turn about 20k with it on 25%.

mtntopgeo

My Feedback: (12)

Darren, Well, you were dead-on, 100% correct. Been flying this thing almost daily, since installing my tall-tank-"fix". Yesterday, about half way through a flight it leaned out badly. Bought it in, topped off the tank, & tried again. That flight lasted about 20 sec. before lean-out, then cut-out. Like a dozen or so times before, tore down the fuel system to the last part. Grabbed the fuel inlet fitting (to the carb) & like a dozen times before, blew into to clear any fuel droplets, then held up to a light. Unlike all previous checks, could not see daylight. Tried to run a pin through it , but met a soft rubbery resistance. Had to use a # 52 drill bit on the inlet, & a #72 on the outlet until I got all this grunge out. I bought the engine used. It was in near new condition (still had a ton of "Norvel pinch" at TDC) But it was probably sitting for quite some time after the original owner ran it. I've cleaned up castor residue before, but this stuff was more like cured 3M Weather Adhesive! ...............Tried the different props mentioned in this thread, & I'd lean towards the 5.7x3 as the best "all'round" prop for this engine/plane combo. ............... Got a little overconfident, & ran the thing with the muffler off, & with a slightly shaved down MAS 5.5x4 (about 20.000 RPMs) Managed to keep the thing up in the air, wide open for the full flight, but really didn't enjoy it. This old man felt like he was about one Dumb-Thumb move away from a heart attack for the full 10 min. flight. .................. Feel that this plane needs about a 2 0z diet, & a flat bottom stick built wing with about 10% more area. Something to add to my list. .................Thanks again for the inputs................. George K.