RE: NGH 9cc Engine input???
 

...I'm gainfully self-employed so the cost of neither the engine nor glow fuel is a big concern. Gas engines have many more benefits besides running cheaper fuel.: They run ALOT better, the tank can be placed at CG, and you don't get slop all over your airplane. I already have a DLE 20 in a Four Star 120 that I like. I'm looking at this engine for a smaller airplane that I already have with a glow engine in it that wouldn't be such a pain in the ass to drag to the field.

The only things giving me pause for this engine is that I'm betting that in 2 years there will be 10 engines in this size range, hopefully including one from OS... and that I've read mixed reviews on the engine. it seems like it's not quite 100% sorted out. I read where one guy got a carb that had a defective main needle seat. This, of course, is the kind of thing you don't have to worry about with an OS which makes them worth the extra $$$.

RE: NGH 9cc Engine input???
 

No need for ignitions batteries. I have been running these units,

http://www.hobbyking.com/hobbyking/s...BEC_3A_5v.html

with a single 6V NIMH pack for the ignition and RX. So far no problems at all.

These are on smaller gassers, 20-someting CC airplanes. You have to work out how much how much the amp drain is for the whole system. Also run a "volt watcher" to see where you are on voltage drop.

Before I went ot these units I was running AAA 4-cell packs for the igntion.

I fear these engines are going to be "slimers" just like glow. Since the con rod is bused you have to run lots of oil. Thus, IMHO... negating part of the gasser advantage.

RE: NGH 9cc Engine input???
 

Ya know,

25:1 is a far cry from 5:1 glow uses.

A velocity stack would probably help with any mess from carb spitting.


T-man49
Club Saito 723

RE: NGH 9cc Engine input???
 

I'd like to know how these little engines work out. I have a 15cc JBA and after I replaced the carb I got it to run reliable, but it is rather heavy. So my .75 size plane does not perform as well as with the same size four stroke glow engine. It has lots of power, but the plane feels heavy.

So a 9cc would be installed on a .40 size plane (?). I don't know how much this engine weights, but I am sure it'll be a lot more then a glow engine.
Most planes this size have a hard time handling the weight. Then there is very little room for ignition box and regulator or ignition battery. It's always a good idea to install your ignition components away from the receiver, and servos.
I think there is a future for these engines, Enya just developed a gas engine which uses a glow plug, no box or extra battery. I think that'll be great fro the smaller planes.

For the planes 20cc and up, my planes all have gassers and I am happy with them.

RE: NGH 9cc Engine input???
 

I just ordered on of these engines. I plan to put it in a P- 40 that I previously had a K&B 40 in. It weighs about twice the K&B but then I had to put in several ounces of lead to balance it before.
The receiver used two 1100ma A123 cells. I will just tap off of that with a couple of diodes for the ignition so I wont need another battery.
Several people have shown that you can use the same battery for the receiver and the ignition if you are using 2.4GHZ

RE: NGH 9cc Engine input???
 

Engine gives ~12K with a APC 11-7 prop and a lot mineral oil mix.

RE: NGH 9cc Engine input???
 

Thats about what I used to get with a 60 size glow when I used them.
I hope the one I get does that good.

RE: NGH 9cc Engine input???
 

RCexl states that the CDI module draws about 650ma when it is running at speed, So you can plan for around that for power consumption when deciding how much battery capacity you need to power the ignition module with. They say a 4.8v nicad pack of about 800mah capacity provides a good hot spark with the system.
<cite>ref http://www.cncengines.com/rcexelcdi.pdf</cite>

here is a discussion about power requirements with the ignition modules too.
http://www.rcuniverse.com/forum/m_10...m.htm#10527705

RE: NGH 9cc Engine input???
 

9cc makes it about a .55 cubic inch sized engine. So isn't all that far away from being a regular .60 engine. My example of the NGH 9cc engine is turning a 11x6 prop at about 11,500 rpms. But it is still relatively new and being run in still. I haven't tried a 11x7 yet. When I last tached a Fox .45 glow RC engine, I was getting around 12,500 RPMs with it using a 11x6 prop and its stock muffler. So I feel the gasoline 9cc engine runs about like a 40 to .45 glow engine. Now the NGH engine might do better if I changed the ignition timing a little, maybe advance it very slightly or or less. But since it was running pretty good like it is, I didn't try that approach.

I have myNGH engine idling as low as 2,500 to 2,600 rpms OK. below that and the engine tends to develop too much of a surge like effect to it. Sort of like a old time WWI fighter plane with the pilot cutting the ignition on and off to taxi the plane around. It might be the RCExl ignition with the advance RPMs trip point set a little too low or high thus it puts the engine on the edge of advancing or retarding the ignition around that RPM speed.

RE: NGH 9cc Engine input???
 

Hi Earlwb,the mother of that GT9 block is JBA56 glow as you know.My JBA 56 engines, give ~13200 RPM s with 11-6 non APC prop and no nitro,full castor self mix fuel.
My measurement gave about 12K RPM s at gas.(I played with ignition timing also)

RE: NGH 9cc Engine input???
 

I got mine today.
It looks like a quality item for only $179.

RE: NGH 9cc Engine input???
 

Just ordered the NGH 9cc the other day. Looking forward to flying it.

Jeff

RE: NGH 9cc Engine input???
 

DirtyBirdy and Stroker280,  do let us know how it goes with your engines. Whether it is good or bad.

RE: NGH 9cc Engine input???
 

Got mine the other day but haven't found time yet to run it. First observation after taking it out of the plastic bag was the motor felt gritty when I turned it over. Flushed it out with WD-40 and much better. I really don't feel like it was dirty on the inside but maybe the piston was dry and made it seem that way. Also I swapped out the prop nut for a better machine grade nut. Will run it this weekend but sure I'll be satisfied with it. Got it at a good price and it will be cheaper to run than Nitro.

Jeff

RE: NGH 9cc Engine input???
 

I want to warn you on GT 9 again because I just met same situation again on last weekend.
Pls. be warned,the prop driver of GT9 can be mount 180 degree forward that makes engine impossible to run.(Simply timing error).
So please check your magnet meets hall sensor during compression phase.

RE: NGH 9cc Engine input???
 

Yes that is a good idea to check the magnet to ensure it is a top dead center matching the piston with the piston is all the way up. Especially after bolting on a propeller. The prop drive washer could slide or slip around the crankshaft as you are tightening up the prop nut.

RE: NGH 9cc Engine input???
 

Good item to pass along. I saw this on mine when I was bolting up the prop and have it set right now.

Jeff

RE: NGH 9cc Engine input???
 

I bought a GT9 a couple of weeks ago and put it in a Phoenix Decathlon. I ran about 4 tanks through it on the ground before I mounted it in the plane. I got a chance this weekend to maiden it. I can't say I was overly impressed, but it handles the Decathlon okay. Tuning the motor seems to be a little troublesome. When tuned for peak rpm, the engine would die when the planes nose was pointed up. I had to set it rich and it would run okay, but it started to miss a little while flying. I tuned it again prior to the second flight and the engine ran much better in level flight, but as soon as I put the plane through any maneuver the engine would start to sputter. Fortunately it never died, though.

I'm planning to take it out again this weekend and experiment with it. I bought the motor simply out of curiousity. I really like the idea of a small gas engine like this.

dbspl

RE: NGH 9cc Engine input???
 

Hi, what was the distance of the pump to carb at your installation?


I am waiting stubbornly if anybody will test that little engine with a pressurized tank and glow type muffler instead of pump.I still hope better results.

RE: NGH 9cc Engine input???
 

I wonder it it is possible to setup a bubbleless fuel tank like the Nelson fuel tanks or not.
I think that would pretty much eliminate the risk that a fuel tank might ignite from the exhaust coming from the muffler. Plus you get to use muffler pressure too. I don't know if the plastic bag in the Nelson fuel tank is gasoline resistant or not.

Granted the risk is fairly low that one could get a fuel tank to ignite using muffler pressure. But there have been a few cases of someone getting a glow engine fuel tank to ignite when they were trying to start their glow engine. So there is some risk there in any case. Especially since gasoline is more flammable than methanol. Now we have also been using muffler pressure with model diesel engines and it hasn't been a problem, but ether is quite flammable too. But I haven't read of any reports where someone got a model diesel engine fuel tank to ignite yet.

But a bubbleless fuel tank setup might be the best way to go.

RE: NGH 9cc Engine input???
 

We visited the idea of pressuring the tank from the pipe on the gas r/c boats. The walbro carbs have a fuel pump built in so there was really no benifit or advantage of using it. One thing to consider is if this is used for example on a plane and the plane quits running in flight is the tank will depressure back into the hot muffler. A inline check valve would be a must but if the carb has a built in fuel pump there is really no advantage.

Jeff

RE: NGH 9cc Engine input???
 

True, but the 9cc engine has the fuel pump separate from the carb. Also the carb and engine seem quite content to draw the fuel OK at WOT if the pump pressure line from the engine comes loose on you. I had that happen a couple of times when I was bench testing the engine. I was thinking that if we can come up with a NelsonStyle bubbleless fuel tank we could use muffler pressure OK then.

RE: NGH 9cc Engine input???
 

Sir, high tempreture might damage the diaphragm if pressure from muffler.