Hi Guys,

What do you think about this color? Too rich, too much oil, or else? This is a 3W 80 with 1:50 oil.

Thanks.

Onewing

rich

check this out http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

You really need a better picture, I fixed it the best I could.

Is the little aluminum balls on the edge of the plug? The center electrode is almost all white in my picture. I got this chart from Pe's site for reading plugs.

Rich, We had an engine (116 MVVS) quit with white fluffy deposits on both plugs.
Turned out to be burnt small aluminum debris that came from the carb trumpet flange (By 3W) we had used in order to fit an air filter.
You better check where those metal parts come from. You don't want to loose your plane when the engine quits in a low hover.

@ Pe

Pe it's Onewing's plug, I just lighten the picture so you could see in the plug. I agree little blobs of melted aluminum on the plug is not a good sign.[X(]

Wow...rich.

That chart is quite nice, but it lacks the lower isolator mixture ring which helps defining hot or cold plugs when reading for mixture. See the picture that tells the "low-down" story. The DJ6J plugs were too cold for that engine, they read black with lean mixtures.

Now that I look at it again, those "globs" are a fata morgana from autocontrasting the picture I suppose?

I think he really needs to post a better picture, looking at what he posted it looks like LawnBoy and overly rich, but when you lighten up the picture the insulator looks white.

Guys. Thank you for your comments. OK, here are two more close up pictures. What do you think.

Thanks.

Onewing

The pics are quite shady and show little detail. From what I can see the plugs look sooty, as for too rich mixture.
I think you need to improve the light so it shines down into the plug. Also angle the camera to look down into the plug. 30 degrees off the plug centerline is about right.
Sunlight at high noon is best, but LED torches also are well suited.
Bulb light is no good for photographs

Agreed.

Your original question doesn't tell us what tuning process you've done. It is very easy to have this kind of plug simply because the carb hasn't been properly adjusted. If your carb is properly adjusted, and the plug looks like this, there are some other more serious problems in your engine.

Looking at that plug, and I have taken Pe's advice on this learning from him, there's little question it is rich. Follow the best carb procedure for tweaking that you have, fly it some, then take more pictures, if you like.

The fact is the plug tells you the state of overall tuning of the engine; there is hardly anything better to tell you. Tweak it.

I'm with Pe on not being to tell because of photo lighting quality. Poor lighting really screws with a plug appearance while trying to lighten the photo later makes it even harder to tell.

First impressions in both photo sets leads you to believe the tune is rich but the center insulators are not well presented due to lighting. That's a very important part of the plug to be left out of the view when making a determination. As is excluding the base of the insulator. So I can't tell much of anything from any of the photos so far,

Not hard to obtain a good picture. Worst case take them outside and shoot in the sunlight.

Again, thank you guys for the comments so far. That's right, I need to provide pictures with better lighting. I hope the following two pictures are more useful.

Also, this is how I have adjusted the engine so far:

1. The engine was bought new from Aircraft International two and half years ago.
2. I broke it in with Lawn Boy at 1:32.
3. Then I switched to Amsoil at 1:50.
4. I have leaned the high end needle about 1/8 turn.
5. I have never touched the low end needle.
6. This engine is on a 33 pounds Ziroli P-40. I fly very conservatively. My flights are usually short, about 5 to 10 minutes.

Thanks again. Hopefully with the better pictures and a short history about this engine, I can get more help from you guys.

The carb setting is too rich, probably on both needles.
First lean the idle needle, until the engine just about fails to cleanly accept throttle horsing. (quick forward stick). That would be the right needle setting.
Then fly, and check the plug again. The idle leaning will also have leaned out full power a bit. That is why you first have to get the L-needle right.
Full throttle flight should have the engine running cleanly, even on speed downlines. Uplines should be without sagging.
Try to chop the engine while at full bore, and glide in and let the engine cool down to check the plug.
Never put a wrench to a plug on a hot engine. That will damage the threads.

edit:
PS, I have a servo delay on my throttle servo. For the abovementioned method I set the throttle speed to 100%. I then move it back to 70% speed, and my warm engine will then accept horsing the stick without a hickup.

Before the next run, get a new plug rather than fight with this one. This plug has experienced some harsh environments that will be difficult to recover from and still provide useful information. As Pe noted, you have a ways to go with the tuning. I won't comment on your oil selections.

Hi Pe and Tired Old Man,

Thanks for your comments.

I put in a new plug and did some tuning this afternoon. I did my low needle first. I was able to lean it almost 1/4 turn and got a steady idle at 1560 rpm and a quick response to "throttle horsing". I also leaned the high needle 1/8 turn. I then flew the airplane for about 10 minutes. I like the low end a lot better. I did not notice much difference at the high end, as I almost never use near full throttle on this bird.

Overall, I am glad I waited for your comments, made the adjustment, before I flew again. Do you guys recommend checking the plug after a few more flights? Or check it just after this one flight?

Thanks again.

Onewing

If you like it , leave it there.
It does not hurt to find the lean limits though. The engine will reward you with best power and lowest fuel consumption. Longevity of the engine and spark plug will also improve because the engine and plug stays cleaner. Less goo to clean off your plane as well.

Better to tune for the best performance against leaving it rich to "protect it" Nothing is saved by running rich. In fact, flight safety is jeapordized because the engine may have a greater propensity to flood out the plug and stall. [link]http://www.zrcgf.com[/link], and Pe's site have several articles between them that address engine truning. Rather that do all the typing it might serve you well to visit them and spend a few miuntes reading. It could make things a lot easier for you.

Pe and Tired Old Man,

I agree with both of you. I will invest some time to get my engine tuned. You are absolutely right, an overly rich setting is not a protection at all.

Thanks.

Onewing

Looking at the washer I think you also need to check the torque.

Ray

What is the proper torque for the spark plug?

Greg

Look on the plug wrap. The ones I know state wrench tightening angle, not torque.