Consistent engine run - upright and inverted

[Dennis Toth]

Guys,
Been working through a problem with consistent engine run upright - inverted and through maneuvers. The engine is an OS baffled 25, side mount on a Ringmaster. I've been flying this ship for 20 yrs, it has had four different motors. First was the old Fox 35, then an OS F20, PAW 15 and finally the current OS25. The OS 25 was a good compromise of weight and power.

A few months ago things started to get inconsistent going to the inverted portion of maneuvers. I started to move the tank and things kept getting worst. Finally, after several searches found a hint that one of the symptoms of a plug going bad was the engine going rich inverted. After changing the plug and getting tank back to the original position all came back to consistent running. 

Best,   DennisT

[Motorman]

If you get a chance try the Merlin plug 2005 hot. High quality made in usa by control line flier Al Kelly. http://www.merlinglowplugs.com/


MM

[Tim Wescott]

My baffle-piston OS 25 just wasn't enough for my Ringmaster -- what's the plane weight and line length, please?

[Dennis Toth]

Tim,
My OS 25 is very steady on my Ringmaster. The ship is 33oz, 59' C to C 0.015" lines. I am using 10% Sig Champion fuel with 2oz of added Klotz (I run this in my Fox's also), venture is a 0.257" with a ST NVA. I use a Top Flite 9x6 clipped to  8 3/4" diameter (I was having a lot of cracklings with the full 9x6 in the 90F + temps so a little less load cured that. Lap time is 4.9 sec.

Best,   DennisT