Guys,
The reason for the question is that I'm having a runaway issue with my Fox 35 in my El D. I have a Randy Smith PA-fox NVA, uniflow tank, 7%N/ 27% oil (50/50), Fox muffler, Sig RC plug, 9x6 APC prop. Issue is that it starts a little rich then as it warms on the ground breaks into a screaming 2 cycle. All efforts to richen have no effect. I had the needle out 5 turns from where it ran rich at the start and made no difference. I tried muffler pressure and still the same (one flight it went way rich but after that just kept screaming). I tried open vent, no change.
This motor has the bypass partially filled with JB Weld (in place of the stick). Could the JB Weld be adding to the heat causing the runaway? Could going to a colder plug (like an Enya 4 or 6) claim it down?
Best, DennisT