Hey fellow r/c drivers, thanks for the advise. The engine is 3 months old. It seems that the glow plug could be the cause. Oh DJ Apolaro, when you mention 1/2 turn bottom, 1/4 turn top you mean clockwise or counter- clockwise? Yeah, I hardly see any smoke. If the engine is overheated, other than the glow plug, what kind of damage can be inflicted on the engine; permanent? BTW how do i know it is the time to change conrod or bearing? So far i have never disassembled an engine. Is there any website that offers such advice?