Sport_pilot,

Your last input was right in general.

I must add; I had an HB.40PDP engine that after being stopped, if you did not wait too long and it was still hot, would start spontaneously if you just flipped the prop, without connecting power to the plug. The catalytic reaction is that strong.

The catalytic reaction of the Platinum catalyst, on the gasoline substrate, in a model engine type glow plug, is too weak to keep it hot enough for ignition, despite the higher flammability of gasoline.

The SmartPlug does use a catalytic ignition process, but it is different from what exists in an OS No.8, although it is not explained in the thread, or the web site.

Sincerely,