I have the third needle for the 60M carb... Now what?

[marked23]

I bought that third needle for the 60M carb. This is the carb that comes with the OS91 csps... and that's the engine I have.

Now that I've complicated my life with another engine adjustment, I need to learn how to set it. I have it all flyable now, but the power just isn't where I was expecting it to be. Doc's YS setup made me look slow today.

What order do I set the needles? How do I know I have each needle set up properly? I'm particularly confused about how to tell if the high-speed needle is rich/lean.

-Mark

[DavidH]

The needle you installed controls the mid range.
The needle works opposite than how normal needles work.
With this needle, you screw the needle counter clockwise ( out ) to lean the mid range mixture. The needle screws clock-wise ( in ) to richen the mid range.
With 30 % Cool Power, a good setting to start with, is 1.5 turns out from fully closed, plus about 3 more clicks out.

You should be able to adjust the main needle now a little leaner. This will allow the high end to be a little leaner. Then the mid range bypass needle can keep the mid range as rich as needed.

David

[R-4-L]

i just bought this engine, could you guys point me on where/how to get this third needle?

[marked23]

Thanks David,

But how do I know when the high-end is too lean? Does it make a different sound?smoke? heat?

Previously, I just set the mix to something that didn't lean the mid-range... and I presume that was way rich on the high end. So as I lean out the high needle, how do I know where to stop?

-Mark

[R-4-L]

sorry mark i didn't mean to hijack your post

[WillJames]

Ali - here is a topic that shows the needle and DavidH lists the part number as:
29081910

http://www.helifreak.com/about1817.htm

[R-4-L]

thanks alot william

[WillJames]

Your welcome Ali. Dean tells me you have a lot of talent and are really getting good. Congratulations!!

If your C-Spec PS is lean in the mid you can also use something to restrict the fuel flow back to the tank on the return line. I have seen Clint help people by soldering up a filter then poking a very small hole. I ahve seen him crush a servo eyelit and put it inside the return tubing, there are a lot of ways to restrict the return flow and achieve the desired result.

The most extreme way to solve your lean midrange is to get the OMI Carb/Cline and remove the pump completely. ;)

[sumonzu]

I set my third needle 1 turn. Go then leaning (closing clockwise) the main needle 1-2 clicks at time from 1 1/2 turn from full closed. Do not be scary to lean the main needle until you get the power you expect... You will end up with an awesome power at full throttle! I ended up at less than 1 1/4 main needle with Cool Power 30%. Please report if that works for you too.
In order to know if you are running too lean you should mesure the engine temperature, mine (head) is about 180-190F (someone says you can go up to 210F but this is still an open question).

[WillJames]

as sumonzu said, go ONE or TWO (preferrably One) click at a time, as the sweet spot is about one click from the last non sweet spot. I run my heads the same temps as well, about 180-190 and get PLENTY of power.( I do run Viper Heads though)

There is a BIG difference in power from a few clicks rich to sweet spot, but there is also about the same number of clicks from sweet to way to lean. Once you get close definitely do one click at a time and fly to test. Also since you are not running the cline, you may find that you have to needle a little rich at full tank to keep it from going lean by <1/3 tank by a click or so.

Good advice sumonzu. :noteworthy

[R-4-L]

William, thanks ! dean is exaggerating a bit ! , I just deeply fell in love with this hobby!

[marked23]

So far, I have never had any issues (knock on wood) with the engine going lean as the tank runs down. It doesn't go lean until the header tank goes dry.

I'm going to have to spend a day at the field learning where my needles are set and writing stuff down. I have a fun-fly this weekend and that will likely be my next chance to work on this.

Thanks Sumonzu, that's something I can work on.

-Mark

[marked23]

Well, I don't have any news about my needle settings lately...

Last time I went flying I crashed two minutes into my first tank. I misjudged my height right at the end of an auto. I was agressively flaring to the side (like I usually do, to land tail-in from a side approach), but I was too low and a blade grabbed the ground. Still landed on the skids, engine running.

Busted:

blades (just one actually, like that helps)
boom ($43 for a boom? really?)
main shaft
feathering shaft
flybar (paddles seem ok, but I bought new ones in case)
head links (now replacing with HD)
stripped 9251 (bought a whole new servo, sending other to service)
stripped 9252 (replaced gears)


What's weird is that I didn't break anything attached to the boom. The torque tube, tail-rod and everything else came out fine.

I did buy new gears for the 9251 (by getting the 9253 gearset), but I'm not happy with my work. Putting it all back together, it seemed to be an imperfect fit, case-wise. Also, the motor sat there at the scene of the crash, all stalled out, for a few minutes. I want Futaba to check that out before I trust it.

So $400 later... I should be back in the air this weekend and maybe I'll get to work on that carb. I bought some Enya #3 plugs to compare against my OS #8s. I wonder if that will change the equation.

-Mark