Originally Posted by Kmot

The engine has a real nice sound to it.

Is that some of the infamous 'black goo' we have heard about, coming out the front of the muffler at the screw head?

Yes some of it was pushing out the front of the muffler around the bolt head. It was tight but maybe it needs a better seal...if there is one at all.
The wind was strong, blowing toward the right side of the plane and that helped to coat it too !
I'm not worried about it. The engine will break-in eventually and it should diminish a bit.

Originally Posted by flyinwalenda

Wow why the personal attack ? How do you know what setting the hs needle is at anyway? If it's that big of a deal it is about 1/2 a turn out from the specs. Geesh !

Fly,


You seem to be no newbie and I expect you to know what you are doing...

Yet, should I suspect that you cannot you tell from the sound the engine makes, that it is running too rich???

With any two-stroke engine running at a correct mixture setting (i.e. two-cycling), its sound will be a clean, uniform 'buzz' typical of this type of engine.

When it is running slightly rich of peak, as the manual states is the proper setting for break-in, an occasional 'miss' will be added, making the sound slightly less clean and RPM will be reduced some 500-700 RPM.

When running very rich, some more docile engines revert into a rather uniform four-cycle; actually firing on alternate revolutions while losing 1,200-1,800 RPM. This, while some stronger, radically timed engines cannot really go into a constant four-cycle and simply make a very non-uniform sound, also losing about the same RPM - this is what I hear from your run of this engine.


And my diagnosis is not dependent on the exact number of turns the HS needle is open. It sounds too rich rich and therefore it is running too rich (and also, probably, not at full throttle), whether the needle is 0.5 turns open, or 8...

So, you are wrong and I urge you to it correctly.

I've a handful of small gas planes, three Zenoah 20cc, a G-23, couple of G-26, a JC-28, and MLD-35 and run 40:1 fuel mix in all. The G-20 engines produce almost no soot but the others some a slight bit to a moderate amount on the MLD-35 which happens to run rich mid range. Clean up after a day of flying requires dampening a folded paper towel with a slight bit of mineral spirits and a minute to wipe the specs up, in the few areas that they are deposited refolding the paper towel to a clean side occasionally. In a nutshell, no hassle whatsoever other than it has to be done outside as mineral spirits are odorous.

Comparatively, the pictures show gross amounts and if typical will be killers for me with this engine. I'm also concerned that with these amounts that there could be some difficulty keeping the muffler pressure port and line open.

I agree that one of the videos sounded like the engine was running rich and therefore the result was not typical. Perhaps one of the HH guys can offer if the goo is typical to their testing. Frankly.... I'm a bit dismayed.

Originally Posted by DarZeelon

So, you are not doing it right and my interjections are not a personal attack!

I urge you to get your act together and do it right.

So calling someone a stubborn @-hole and telling them to get their act together is your idea of "helping"......all over watching a video ? Glad I have thick skin ! Tell you what....you break-in your engine your way and I'll break-in this one my way and I won't put you down when commenting on it.
How many of these new engines do you currently have?

Fly,


There's a slight difference between calling someone a name; and saying that if he maintains a stubborn attitude and continues doing it wrong, he'd be worthy of that title.

Just do it the right way and I will not expect you to tell me (or all of us) about it.

If you select not to take the right course, it would take ages for this engine to be fully ready...
...And then I guess you would probably consider it an engine that requires a long break-in period' rather than fault yourself...


I have written about 'break-in procedures' that were prescribed by some engine manufacturers, as 'a preparation for overhaul'... But what Horizon Hobby prescribes in their manual for this engine is right to the point.

I strongly suggest that you do follow it, rather than doing it 'your way'.

The "black goo" as everyone calls it is very typical of break-in. Most of the "goo" for the first several tanks is actually little pieces of metal that are wearing away from the surfaces that are being mated by the break-in process. The "goo" should decrease a fair amount and change more from black to a lighter brown after the engine becomes more broken-in. It won't go away altogether though because there is too much oil in the fuel. As the engine breaks-in it changes from being small amounts of metal to being un-burnt oil - hence the change in color and amount. The reason you don't see so much residue from the larger airplanes is mostly due to the lower oil content in the fuel. If you redirect the exhaust you can greatly reduce the amount of residue actually on your airplane.

Dar - We haven't "cop-ed out"...I'd say we're watching from a distance and answering questions that actually are looking for answers ;-)

Thanks,
Jimmy

Horizon Hobby, Inc.
Saito, Evolution & Zenoah Developer

Originally Posted by AA5BY

I've a handful of small gas planes, three Zenoah 20cc, a G-23, couple of G-26, a JC-28, and MLD-35 and run 40:1 fuel mix in all. The G-20 engines produce almost no soot but the others some a slight bit to a moderate amount on the MLD-35 which happens to run rich mid range. Clean up after a day of flying requires dampening a folded paper towel with a slight bit of mineral spirits and a minute to wipe the specs up, in the few areas that they are deposited refolding the paper towel to a clean side occasionally. In a nutshell, no hassle whatsoever other than it has to be done outside as mineral spirits are odorous.

Comparatively, the pictures show gross amounts and if typical will be killers for me with this engine. I'm also concerned that with these amounts that there could be some difficulty keeping the muffler pressure port and line open.

I agree that one of the videos sounded like the engine was running rich and therefore the result was not typical. Perhaps one of the HH guys can offer if the goo is typical to their testing. Frankly.... I'm a bit dismayed.

Originally Posted by jspauld2

Dar - We haven't "cop-ed out"...I'd say we're watching from a distance and answering questions that actually are looking for answers ;-)

Thanks,
Jimmy

Horizon Hobby, Inc.
Saito, Evolution & Zenoah Developer

Jimmy,


After you posted the RPM table for this engine in post #54, you 'stepped on my toes' so to speak, when you and your team suggested the in-flight RPM numbers can be used to calculate and plot the HP curve... When I challenged it you 'left the building'...

I appreciate Horizon Hobby's choice of manufacturer for smaller Evolution two-stroke engines.
I appreciate the break-in procedure you specify for it also, having written and begun this thread.
I represented and dealt in Israel for the manufacturer of your larger two-strokes; MVVS, for several years, until I transferred it to another.

In the last couple of days, when I found the carburettor of this new engine does not have a diaphragm pump, I once again protested, since I am quite sure the pump is crucial. Unless, that is, you want this engine to be 'more of the same' for glow people.

If you like us to discuss the issue further, let's go to the PM system.

Dar,

All I simply meant by the comment was that I've been paying attention the entire time. I chose to be an observer of the conversation and step in when there was a specific question that I could help answer.

You were correct in your statement about the in-flight numbers I posted as being of no use for HP calculations, that was my mistake and perhaps I should have admitted that to you. The numbers can be useful in determining whether or not the engine would suit your purposes for your particular airplane.

As for the pump.. throughout development we were well aware of the perceived issues with not including a pump on the carburetor. We spent countless hours developing and testing the engine and are quite satisfied with the current system. We have found (as have others posted on this forum) that the engine performs well in all attitudes and orientations. No matter what theoretically should or should not work we have tested and found that this setup does.

There's no need to headbutt knowledge of theory on the PM system, I am simply here to answer questions, not debate knowledge.

Thanks,
Jimmy

Originally Posted by DarZeelon

Jimmy,


After you posted the RPM table for this engine in post #54, you 'stepped on my toes' so to speak, when you and your team suggested the in-flight RPM numbers can be used to calculate and plot the HP curve... When I challenged it you 'left the building'...

I appreciate Horizon Hobby's choice of manufacturer for smaller Evolution two-stroke engines. I represented and dealt in Israel for the manufacturer of your larger two-strokes; MVVS, for several years, until I transferred it to another.

In the last couple of days, when I found the carburettor of this new engine does not have a diaphragm pump, I once again protested, since I am quite sure the pump is crucial. Unless, that is, you want this engine to be 'more of the same' for glow people.

If you like us to discuss the issue further, let's go to the PM system.

Hi Jimmy, I'm in the UK and have an engine on order so I'm eagerly awaiting their arrival on our shores. What I would be interested in is any noise test figures you have, if you have a comparison with another brand even better. If you have figures at 7 metres even better still.
The club I fly with have quite strict noise limits so I won't be able to run the engine in in the air using a 10" prop, not a chance! I'd be hung drawn and quatered for that!

Bob

Bob,

We have done some noise testing, but we don't have very sophisticated methods to measure it. Pete B. would be able to give you a more detailed answer to your question however.

My best guess for you would be that you won't be able to use a 10 or 11" prop at your field, they both wind up very well. The 12 and 13" props are probably getting closer to your needed sound range. If I'm able to, I will try to get some sound measurements, but it's ~30°F here so it might be a while before I'm able to get any figures for you.

If you contact Horizon UK they might be able to help you faster and they're more knowledgeable about your noise restrictions!

Originally Posted by BrumBob

Hi Jimmy, I'm in the UK and have an engine on order so I'm eagerly awaiting their arrival on our shores. What I would be interested in is any noise test figures you have, if you have a comparison with another brand even better. If you have figures at 7 metres even better still.
The club I fly with have quite strict noise limits so I won't be able to run the engine in in the air using a 10" prop, not a chance! I'd be hung drawn and quatered for that!

Bob

I appreciate your reply, Jimmy.
Happy New Year's Eve.


Dar Zeelon

Thanks,

Same to you!

Originally Posted by DarZeelon

I appreciate your reply, Jimmy.
Happy New Year's Eve.


Dar Zeelon

Originally Posted by jspauld2

The "black goo" as everyone calls it is very typical of break-in. Most of the "goo" for the first several tanks is actually little pieces of metal that are wearing away from the surfaces that are being mated by the break-in process. The "goo" should decrease a fair amount and change more from black to a lighter brown after the engine becomes more broken-in. It won't go away altogether though because there is too much oil in the fuel. As the engine breaks-in it changes from being small amounts of metal to being un-burnt oil - hence the change in color and amount. The reason you don't see so much residue from the larger airplanes is mostly due to the lower oil content in the fuel. If you redirect the exhaust you can greatly reduce the amount of residue actually on your airplane.

Thanks,
Jimmy

Horizon Hobby, Inc.
Saito, Evolution & Zenoah Developer

And thank you Jimmy for your response. No doubt that with something new, we each apply our personal wish list as to what it will do for us. Certainly there will be much less exhaust residue from six oz of 5% oil additive fuel compared to 12-14 of 18%.

Additional steps to divert aren't as problematic on these size planes and we'll give effort to that end and see how it goes.

thanks Jimmy, I'll try an email to .UK.
Happy new year to all,
Bob

My Saito FG-14 produced quite a bit of "black goo" for the first couple gallons of fuel. It is also running 20:1 Amsoil pro. After a good breakin period the goo has all but disappeared. Now I just have a couple of tiny specks on the plane after an hour or so of flight time. The exhaust is simply a Saito 90 elbow out of the head, pointing straight back. No muffler, and it sounds SWEET, not too loud either.

Before someone beats me up: The Evo manual says NO Amsoil, so I am running it with Castrol MC oil.