turbojoe

My Feedback: (8)

I've broken it in by the book. Actually about 4 tanks through it so far (no flights). I can't get a good balance between idle,transition and wide open. I can get two of three but not all three. I think it's all in the needle settings. When I bought the engine N.I.B. from LHS the idle mixture was screwed all the way in. Through LOTS of trial and error I've finally gotten close to good settings but just not completely right. The idle mixture screw was definitely waaayyy off. The high speed needle has to end up at about 1 1/4 turns where the manual calls for 2 1/2. Moving one needle affects the other so I'm looking for a baseline idle mixture setting from a good running engine. Can someone pass on the amount of turns on their XL-46 idle screw so I can get mine a little closer?
I have no air bubbles in the fuel line and I can kill the engine easily with the trim (too easily) I can't get a low enough idle without it quiting. I'm running 15% nitro and have tried several glow plugs. I'm sure it all lies in the adjustments.
I should also add that this is the earlier model not the XLS and it doesn't have the remote needle valve.

w8ye

My Feedback: (16)

There are variations of tolerances in the manufacture of the needle valves and you have to get the engine to run right. It may be 1-1/4 turns and it may be 5 turns.

You want to start over and set the idle in the right general area first. There is a thread in the manufacture's section by Ann Marie Cross that explains how to do this. It involves taking the carb out and listening to it in a quite room. Hook a piece of fuel line to it and with the throttle closed to what should be a good idle position, open the idle needle to where you can just hear a little air blowing out when you blow in the fuel hose. This will give you a ball park setting. Then put it back in the engine and see what you can do with it.

If this sounds too hi-tech for you, you can open the idle screw 2-1/2 turns and go from there.

Good luck,

Jim

rcflier_gi

My Feedback: (2)

Are you running muffler pressure to your fuel tank? My Magnum 2 strokes like to run on Thunderbolt Hot glow plugs.

turbojoe

My Feedback: (8)

W8ye. Not gonna happen. To much time around jets in the Navy took away much of my hearing.

rcflier_gi . I'm running muffler pressure and a Thunderbolt hot plug.

Don't get me wrong it runs great it's just that if I get mid range and wide open right then idle is not reliable. (it'll quit) and vice versa. It seems when the idle is just right then it loads up on accelleration and top end gets rich. I think I'm dancing on that fine line between having it gnats ass and out just enough to frustrate.

I e-mailed Global once before about this and got a generic reply. I'll try again and see if they can give me the initial factory setting. That's really all I need.

w8ye

My Feedback: (16)

Try the idle screw at 2-1/2 turns, If that doesn't work the try 1-1/2 turns.

In your adjustments, just move the idle 1/8 turn at a time and re-try

You should be able to tell how rich or lean it is. Reduce the throttle to just where it starts to run rough. Then adjust the low speed to smooth it out. Keep on doing this till you get it downto where you want it.

If it is too lean (too far in), the engine will just quit when it gets to the point where it is too lean to run.

If the needle is too rich, (too far out), the motor will began to run rougher and will smoke more.

You will have to go back and re-adjust the high needle every so aoften because they are somewhat inter related.

After you think you have the idle set, goose the throttle some and see what it does. If it just quits then the idle is too lean. If it blurbs out smoke and raw fuel it and maybe picks up and starts to run OK, then the idle is too rich.

Rather typical is for the midrange to seem a little on the rich side when everything is set right.

Good luck

Jim

Mighty Mouse-RCU

My Feedback: (145)

Put a few more tanks through it. The xls can take a while to break in. Not too rich mind you.

turbojoe

My Feedback: (8)

This is not the XLS it's the earlier XL.
I just checked and with it running the best yesterday the low speed screw is out 9 1/4 turns. Most likely way too far. I went through 2 tanks yesterday playing with it. I'm just not gonna mess with it any more until I get a factory baseline setting. All of the links on the Global/Magnum site are dead right now so I'll have to keep trying them.

I also have a brand new XL40 with the remote needle carb. I'm thinking of putting its carb on there for now. I've got a new Irvine .53 too. I wonder if that carb will fit? I haven't measured any of them yet. I don't want to open the bags they're in. That Irvine is too pretty to get dirty.