Hi

I could use some expert guidance to help me get my RCGF gas engine to start. I am a complete noob to RC engines so I've been slowly trying to work out what's going on and I've got somewhere but it still won't start.

So, the engine is an RCGF 15cc and I've been trying to get it started for the first time. I have got as far as getting it to fire enough to spin the prop and a couple of times it had enough momentum to fire a second time but that's it. I know it's been firing because i get some oil smoke out of the exhaust. I've uploaded a video to show what happens most of the time -but I can't attach the url... Occasionally it sounds a bit louder and seems to have a more powerful firing but its still not enough.

I've been adjusting different aspects to try and work out what's not right and i've worked out that:
-It fires best with 0 to 20% throttle. If it open the throttle beyond that it stops even firing so I assume its getting flooded.
-Adjusting the spark timing makes a difference. I can get it to fire best when around 30 degrees, it also fires when advanced a bit further, but it won't fire when retarded by much.
-Adjusting the idle position has no noticeable effect
-I've adjusted the low and high needle valves but they don't make a noticable difference beyond stopping any fuel (no firing) or flooding it (no firing)...
-my garage is cold (10c) so I've tried warming the cylinder block with a hot air gun. Not sure it had any impact.

I really don't know what else to try. Please can someone spot my mistake or something?