hey guys, I finally got to fly my alpha trainer .40 today for the first time. The weather was just gorgeous. My instructor flew it around this morning and everything seemed to be perfect. He came back in and made a few linkage adjustments and took it back up once again. When he brought it back in the second time, I noticed oil all over the leading edge of the right wing. I know this is normal but it had a whole bunch of black soot looking stuff in the oil that was on the wing. I didn't ask why but I figgure it is just the engine breaking in. Am I correct? I bought this plane brand new and have it has never been flown. All I have done with it is taxi around in the driveway for about two tanks of fuel.

BTW....I got to fly it for about 20 rounds in the sky today.......what fun it is!!!!

Joe

sometimes if the muffler has a leak you will get more of a black exhaust residue( i don't know why though).

Thats normal-

I agree. It sounds more like the black residue you get when some part of the muffler isn't sealing right. Check to make sure it's all tight, then I wouldn't worry about it.
Dennis-

It sounds like the muffler isn't sealing tight to the engine. It shouldn't hurt anything.

If the residue bothers you, make a gasket to go between the engine and the muffler. FWIW - I also use some locktite on the muffler bolts AND the through bolt in the muffler.

NO, NO, NO !!!

Guys, "a whole bunch of black soot " IS NOT NORMAL !!!

That black stuff is aluminum metal powder. Either something is rubbing inside the engine, or something (maybe the muffler ) is rubbing on the outside. Hopefully it's something like a loose muffler rubbing at the engine joint and tightening the muffler screws will fix it. If it's inside, something needs to be fixed, or you're going to have a sick engine real soon now.

Like they say: "Free advice is worth every penny you pay for it."

I got the same thing for the first 2 or 3 tanks through my Supre Tigre... Now it's gone and it's running great.

Don't know if this is considered normal or not, it didn't happen with the only other engine I've bought new, but it did seem to go away after it was broken in.

hebertjj,
You're right about "free advice". It's very unlikely that there's anything going on in the engine. If it were adjusted lean to the point that there was that much wear, it wouldn't stay running.

The most likely scenario by a LARGE margin, is the muffler.
Dennis-

I agree on the muffler. There is very little aluminum to anything contact in the engine proper. If the engine is running fine, the I would suspect something in the muffler is loose. Go over all the screws. I use blue loctite on all the bolts and screws on my mufflers before firing up the first time. Just to be sure the bolts are tight and will stay that way. Had a coupla them fall off on me. So I do this every time to avoid that.

Mark Shuman

It's funny if the instructor wasn't worried about and "He was there" what is everyone's worries.

I have an Alpha Trainer 40 and yes I has some of that same black stuff. It should start tappering off. One thing that's nice is that the Evo engines are sturdy and broken in at the factory.

They have already run the engine and set the adjustments.

What kind of fuel are you using? That may explain some of it.

If your instructor is at all knowledgeable he would have been worried and told you so...and if he is not...

Lefty

i am using powermaster 10% for now. I might use somthing else when i'm ready for it. I think you are right Left, he prolly would have told me somthing about it. I just don't understand how unburned fuel could turn black if there is an exhaust leak.

While he was flying it, I asked him if he has flown this plane before and he told me that he has trained at least 25 people with this exact plane. He also stated that this particular plane flies much better and has a stronger engine than any other alpha 40 he has flown.
I think it might be because I exchanged the three blade prop with a 10x7 wooden master airscrew. Maybe this makes a difference???

Joe

I would agree that a blade change is why you have more power. The three blade is more designed to be good at lower speeds and keep you in control more during landing.

BTW I flew my Alpha again this past weekend and had some of the same stuff still coming out.

I have had my plane for about8 months now.

Lefty

If there is an internal problem with your engine, there will be "sparkles" (metal particles) in the residue. If not, the residue is nothing more than combustion products. The residue will be more blackened if your fuel contains castor oil, than if it has only synthetic oil. It will also be more blackened by air leaks into the exhaust system -- this permits greater oxidation of the hot oil/fuel vapour in the muffler.

If no sparkles -- no problem.

Multi-blade props (three or more blades) do not perform well on models -- they are used to increase ground clearance &/or to provide a more "scale" appearance. You did the right thing by switching to a 2-blade prop.

Enjoy your new hobby.

Brit Brat I have to disagree on the three prop theory...
Three blade props perform exactly like they are suppose to on the Alpha Trainer, hence it's a trainer...

As the Horizon Hobby web site states:

No matter how gentle a ready-to-fly trainer's flight characteristics, learning to manage speed and power is one of the biggest challenges for a beginner. The Evolution system uses a specially designed, three-bladed prop that provides superb climb performance and slower level-flight speeds at high power settings. It's a lot quieter too-nearly 4db quieter than a typical 10 x 6 two-bladed prop. What it all adds up to is a trainer that reduces the beginner's workload by letting him focus more on flying and less on managing the throttle

Lefty