I have New YS 63 mounted inverted, 20/20 fuel, 11.5 x 7 Bolly prop; have posted here before with problems with this engine; dowloaded instructions from performance and followed to the letter; engine starts at 1/4 throttle, will abvance throttle slowly after warming up for 30 seconds at fast idle; good transition and top end, bring throttle back to idle and back to full throttle quickly with fairly good response, but unreliable at times; plane performs well with this engine, lots of verticle, however, when I cut the throttle back to land, the engine will cut out; I have messed with this engine pretty much the whole time since I got it in May, idle for the most part is unreliable, it is no joy flying this plane with such an unreliable engine when it comes time to land, no one likes to deadstick everytime, fortunatley I was landing anyways; would putting an onboard glow that activates at low throttle help, or I keep hearing you tell people to send these engines in because the regulator is sticking; is this the problem with this engine; if I send it in will it be a warranty issue, which should still be valid considering I bought it in May; if this is the case do I contact service for authorization, or what is the procedure. Doug.

Two things to try: 30% Coolpower Heli fuel, or pull the plug element up out of the cavity about .030" with a #11 blade. Either makes the plug run hotter.

Make sure both valves are set at .003". If too tight, the valves leak off compression and won't keep the plug hot at idle.

If neither works, send it.

Any difference using a YS or OSF Plugs; or raise the element on either brand? and is PowerMaster 30% Heli Fuel a good choice, as this is more readily available in my area than CoolPower fuel? Thanks Again.

As stated here before, YS and OS type F are EXACTLY the same plug. OS makes them for YS. The only difference is the packaging and the marking on the plug body. Otherwise they are identical.

PM 30 heli is fine. We use it in service.