Built a 1/4 stand off scale Sig Cub. Inverting the engine was the only way to go. Inverted a 120 Surpass 4 stroke (has pump) and added an on board glow driver (low rpm only). When it is pulled back to idle, it does well for 10 seconds or so, then starts smoking and continues to get worse and eventually loads up and dies. I thought the glow driver would prevent this! Any ideas other than going to a gasser?

Thanks, Bill