ORIGINAL: w8ye
It's runing too lean and about to backfire and throw the prop
w8ye,
I think I found out why I'm having trouble setting the needles on my 1.25. Yesterday I tried to start my PT-26 at the field (Saito 1.20) and the throttle would not move. I found what I thought was the problem, the servo. Today I changed the servo for a new one and I had the same condition. I swapped in a new receiver, same result. More tail chasing. I have two 9C Futaba Tx's. I use one for 72 MHz and the one for the PT-26 has a 2.4 GHz module. I swapped Tx's, using the 72 MHz with the 2.4 module in it. Voila! The original radio's throttle gimbal is not working. I'm assuming it's a pot. I've had it six years. Time for a new one.
The problem with the throttle stick on the Tx is probably the reason I've had trouble tuning the 1.20 on the PT-26 before, and the reason I can't get the 1.25 right. I also had some (what I believe now) power issues with the 1.60 twin on my Cub. I think it all traces back to the throttle gimbal not giving me what I ask for.
Bob