Bill,

I've often wondered about that.

A club mate recommended a short plug in my then new McCoy 35 Red Head, because I wasn't sure I had a long hot plug to use, and some time later I experienced a flame out during a wing over, and subsequent loss of line tension. The crash repair to my SIG Sky Ray 35 was minimal, but the short plug was replaced with a normal long plug typically used in the McCoy 35. The flame out was never repeated?

Seems to me the large empty plug cavity (with a short plug installed), may have been a trap for some of the high Castor oil content of the McCoy fuel, and resulted in flooded plug?

Bill

Randy,

Thanks for the conformation.

Self proclaimed engine experts, are often not to be taken seriously, and that's why I always read your posts, and advice. You have proven time and again that you know what your talking about.

Thanks for all you do for the model engine community!

Bill

Thanks. Flaming out makes sense to me.

  Even if it didn't, you lose power. We (my dad and I) had one engine that would only keep running reliably with a Fox "short" 2V plug, but it was noticeably down on power to the Fox STD long, for the brief moments it would run at all. Last thing in the world you need on a Fox is to reduce the compression.

   BTW, very small/fine compression adjustments on all engines can be made by using an extra glow plug gasket. This was one of the tricks back in the good old days, particularly on the ST46. Most other engines are nowhere near the edge on compression and can use all you can stand.

    Brett