I have a Rossi 61DF engine that is about 10 years old. I am having trouble setting it back up. It will start, idle and run up to about half throttle. If I go higher, it stalls. The carb has 2 needle valves, 1 one the side where the fuel line is connected and 1 on the other side where you connect the linkage. When the fan is out of the plane, it runs great, as soon as I put the fan back in the plane, I have the trouble. I am using a header tank.

Anyone know the basic needle valve settings for this engine?

use 5% fuel...i was having problems with a Rossi 45 recently...i diluted some 15% nitro with fai fuel ...3 parts FAI to one part 15% nitro , now the engines runs much more reliably..... i had the same problem as you

I'm running this in a ducted fan Hawk. The fuel I use, I mix myself and have no trouble in any other of my glow engines. It is 16% oil in methanol, no nitro.
Do you know the initial settings for the needle valves and I can go from there.

Are you using the header tank on the bench? If not then it's the likely culprit. I've never messed with ducted fan engines but from all I've read the fuel usually has around 22% oil. It's wise to increase the oil anyway when not using nitro because of the leaner needle settings needed. I don't use nitro either and never go below 20% oil and that's with all castor too.