Evolution 46 NX
 

I just received an Evolution 46 NX from Horizon Hobby as a replacement for the P.O.S. 46 NT that came with my Hangar 9 PNP 40 size Cub. Basically what are the main differences between the NX and NT and is this a decent engine. I'm a little nervous about flying with this engine as the last one was so unreliable I don't think I had a landing with the engine running. Even on the maiden flight the engine quit in less than a minute after take off. I want to install a Saito Fa 62 in it as soon as funds will allow. Any input is appreciated.

RE: Evolution 46 NX
 

Given proper fuel supply and cooling you should not have had much problems with the NT. It's rare to have a dud. I have several NT's,they are powerful but a tad heavy. The stuff I had some minor issues with were mainly evident at higher than normal rpm use. The long muffler screw loosen or break, the throttle arm would loosen where it's crimped on or staked in place, the tip of the throttle stop screw would break off and render the carb useless and in later models when they went to steel cage bearings the life was reduced.

Could you have had fuel foaming issues? Was the engine in a cowling with plenty of opening for the hot air to exit? If the next engine has problems, you'll know it's most likely your setup in the plane.

I couldn't find much differences NX vs NT....the color of the head?

RE: Evolution 46 NX
 

GlueMaster,


You might want to consult Barry (blw) over these pages...
He should be able to tell you what you are doing wrong...

Evolution glow engines are designed to be very easy to operate; even by a rank beginner, but even they are not immune to mistakes.


Some engines are a bit more of a chore to adjust than others; but if your engine in misbehaving because of your setup, ANY engine that you install to replace it, will give you the same troubles.
Four-stroke engines have stronger power-pulses and thus vibrate more than two-strokes. So, if vibration is the cause of your problem; a four-stroke will only 'compound the pounding' (pun).


You can tell us more about your setup... Where is the tank in relationship to the engine, how long are the fuel-lines, is there foam-padding around the tank, Etc..

RE: Evolution 46 NX
 

Wow I just looked up the manual, That poor engine looks like it could die of heat stroke in there(section 3). http://www.hobbyzone.com/documents/HAN4025-manual.pdf Try and fly it without the cowling first.
If it were me I'd cut a slot in the cowl 3/8" wide lined up and right in front of the cylinder, half way to the crank shaft. Than I'd block off the two small holes in front(round and slot) and open it up more to the rear bottom (each side of the muffler). I wonder if anyone else had problems?


Look like an electric prop they used in the picture LOL.

RE: Evolution 46 NX
 

HEH HEH

There's no way that would work for the reasons stated in the previous post . Is that a 9 X 6E prop?

The rest of it is such a nice plane. Why did they foul up like that with no cooling?

RE: Evolution 46 NX
 

Did you broke in the engine??

RE: Evolution 46 NX
 

The engine came installed in the plane with the cowl cut out and all. I know there is nothing wrong with the fuel system in the plane as it ran the same way on the bench. As far as breaking the engine, is states in the manual that no break in is required however I did run about a tank of fuel through it just to be sure. I tried removing the needle limiters on the HSN and LSN and adjusted them for hours trying to get it to run as well as trying different glow plugs and different fuel. I called Horizon and they said it sounded like bad bearings to them and to send it in as it was still within the two year warranty period. After about a week and a half I called to check the status of the repair and guess what? They said almost every part was replaced including both bearings and they still couldn't get it to run correctly so they sent me a new engine. This one is the 46 NX as the NT has been discontinued. As far as the cowling is concerned there is a largish area around the muffler so the heat can escape. Anyway if this engine doesn't work out I'll go with a Saito 62. My older H9 cub with a Saito 56 flies great and sounds so nice. I almost forgot to say what awesome support Horizon Hobby has.

RE: Evolution 46 NX
 

You haven't even said which prop, fuel and plug are you using...give us more info about it, and then we could help you (try).

If you don't want to tinker with it and try to find what is wrong, it is just a waste of time (no offense is intended)... most people around here have experience and when someone have problems, normally a solution is found, but if you just want to replace it with the Saito... doesn't make much sense...

Saludos

RE: Evolution 46 NX
 

Estradajae, the original engine I was having issues with is gone and I have a replacement for it hence the original question. I haven't flown the new engine yet but I may try next weekend weather permitting. The fuel being used is Wildcat Premium Xtra 15 % nitro, 18 % oil and the prop is a Master Airscrew 11x6 wood. And as stated in my previous post I tried everything possible to get it to run right. Even Evolution tech support couldn't get it to run right so I don't think I was doing anything wrong. The reason for a Saito is the sound and the power as well as fuel economy.

RE: Evolution 46 NX
 

My .46NT and .455PTS are strong engines that run extremely well. I had a model with a TT Pro .46, OS .47FX and the NT on it. The Evo was a far stronger engine from the first tank of fuel.

Your new engine may have a tight pinch. Mine squealed when I tried to turn it over by hand. Also, you can use the installed glow plug for that first tank of fuel, but I would strongly recommend that you replace it with an OS A3. These engines seem to need that hotter plug, and that also includes the .40, .61, and 1.00. I don't know about the .36. It should loosen up considerably after about 10 oz of fuel.

RE: Evolution 46 NX
 

So far it seems to run good. Thanks for the tip on the glow plug. I do have an O.S. A3 that I will install before I fly it.

RE: Evolution 46 NX
 

Did they raise the compression in the NX over NT?

RE: Evolution 46 NX
 

That's what it says on line anyway. They also changed the angle of the glow plug back to normal instead of canted back. Hopefully it will run well and be reliable. Nothing like having a nice new plane and being afraid to fly it because the engine is unreliable.

RE: Evolution 46 NX
 

One way to test for the right plug is to watch how the engine acts when you crank it. Does it sound like it is gargling or like it is sloppy full of fuel when you slowly advance the throttle? Does it want to die out on you when you do that? The A3 fixes this and gives a better burn, so much more power.

If you have real problems running one of these engines, you may have a carb or bearing problem. Normally, these are well running engines that are very forgiving when tuning them. The crankcases don't load up with fuel as much as other 2 strokes, or they burn that excess fuel off better, one of the other.

Some Evolutions were shipped without the O ring for the carb. There was a trouble with those engines a couple of years ago. This was mostly limited to the .61.

RE: Evolution 46 NX
 

Well I finally got to fly the Cub today with the new Evolution 46 NX. What a difference. After priming and a couple of flips it was running and sounded good. I have the HSN a little on the rich side for now until I get some more time on the engine. I flew for almost 15 minutes and not so much as a hiccup. After I landed I checked the fuel and still had around a half of a tank left. At least I can fly it now until I get my Saito Fa 62.

RE: Evolution 46 NX
 

Your flying, good to hear it! Be alert for engine power sag (heat).
Like you said, if you are going for sound, the Saito 62 is way cooler, as for fuel use may be a draw....depending on how you fly too.
A Saito 82 will be a match in power but it will eat more fuel than your Evo.