Hi!
Load up?? You mean you start the engine and it sits running for a while and then stops?

Here is the soulution!
First put an a 11x6 or 12x4 prop, preferably APC.
Then get fuel containing 5%-15% nitro and 20% castor oil (or synthetic or a mix)
If in Europe get 15% synthetic oil like Aerosave or Aerosynt 2 or Motul "Micro".
It is vital that you mount the tank so that when the airplane sits horizontal the center of the tank is inline with the fuel intake orifice in the carb!
Use pressure to the tank, preferably a 2 clunk system called "Uniflow".
You should also use a 240-300cc (8oz-10oz) tank not bigger!
Best glowplug for the OS .40-.46 is an OS 8 or Enya 3 glowplug.
If you have followed the the above recommendations it is not necessary to drill the airbleed hole in the engine. Al OS LA engines run jsut fine as they are.
Standard setting for the idle needle (airbleed) is half way open, but try open it some what if the engine load up at low rpm and stops.
But remember the throttle drum must first be adjusted so that you have good idle. The throttle drum should be 1,5-2mm open at idle.That's the standard setting on all glow engines.
Good luck!

Regards!
Jan K
Sweden