I've had about a dozen or more flights with this engine. Now it has decided it wants to die at idle, BUT only when I'm flying! I ran a half a tank through it the other day, and I couldn't get it to die. But just about every time I come in for a landing, the engine dies. Today, it also died at wide open throttle on take-off. I am still on a buddy box, and when my instructor took over the engine caught. He was at half throttle roughly. I've tried richer and leaner, plus put a new glow plug in it.

I took the engine and fuel tank apart and didn't see anything that looks unusual. The clunk was in the proper spot in the tank.

Any ideas? Should I try a different plug? Hotter? Idle bar?

Thanks

Kerry

Not an expert, but I had similar experience with my 46Fx, and it ended up killing my ultrastick One of the trainers at the field did a mini-tuneup for me after I bench ran it, and had similar results to yours, no problems. What he did is actually turn it upside down when it was running, and leaned ou the low idle screw a bit, then readjusted the needle valve. Been running great since.

Dave

Not much info to go on, have you checked the motor for air leaks?
when you get it started have you tried holding it straight up to see if it dies?
have you checked to see if the low speed jet (air bleed) is blocked.

checked the lines for nicks.

Hey, have a OS .46LA myself, had similar problems a few days ago.

Engine RPM was very unstable, engine would run while the plane was on the ground, but would stop when I lifted the plane, are turned it upside down.

Turned out there was a very small hole in the fuel line going to the carb. I replaced all my fuel lines, and the engine ran great all weekend.

Maybe your clunk has come off, or is forced foward inside your fuel tank.

I have been dogged with problems with 2x 46LA's myself.

How I have eventualy fixed it.

1) use a good synthetic glomix with only 5% nitro - no more.

2) Swap plug to an OS no8 or something like a Model technics F5.

I personaly dont use idle-bar plugs, just std taylor type, but the two other types should help.

Also what size prop are you turning, 11x6 or 10.5x7 I have found to be the best ballance between RPM & thrust.

I still don't think the remote needles are of much good....

your fule line in the tank mite be TOO flexible that will let the clunk roll around in there!

I have almost the same problem with my MDS 40. Runs great untill I point the plane nose-up. Then it dies. What to do??????

This is fuel starvation.

Mixture could be too weak, does the engine RPM's increase with nose down ?

Check fuel lines for air when you nose up, if so then check tank config , fuel lines for small splits.

You pressurised the tank from the muffler nipple right ?