I believe there is a problem with the fuel feed on this motor ( which I'm getting) What is the best method of fixing it please.  Lazza. Australia.

what fuel proportion are you using

http://www.rcindia.org/fuel-and-engines/review-ngh-engines-gt9-(9-07-cc)/msg85549/#msg85549

I have added lot of details on this thread. go through and shoot out your questions if any

My brother also noticed this problem, where if the carb is mounted on the engine, the fuel becoming vapors was causing bubbles.  He moved the carb from the engine to the aircraft frame, and life has been good ever since.

Just an update on the NTH 9cc petro  engine.
After altering the magnet to make the spark at top dead centre or just before, and a fair bit of trial and error with the throttle controle and the high speed needle I have now got it to start and run as I please.
What I found is, to start it I adjust the HSN to only just open and the throttle arm at about a 1/4 open. Then opened the throttle a little and at the same time opened the HSN a bit , then a bit more and so on untill after a tank and a half the engine will run at 1 complete turn of the HSN and almost fully open throttle. When I throttle back it slows down but at 4 stroking. As it gets run in I think it will tune out OK.
 At present I'm punning it on 20/1 Petrol/oil and a 10X6 inch prop. or 255mm X 153mm. I intend to increase to 13X 5  or even 14X 4 according to the article in Airbone mag. 242.
Also I'm using the starter.  With a larger prop it should start by hand I think.  Makes quite a screem with the 10X6. Thanks for all the posting on this motor, very helpfull, as I'm not alone . Lazza