Originally posted by ecajberry
Today I fired up a New OS 46fx to run a tank of fuel thru it before its maiden flight next weekend.
This thing was VERY sluggish on throttle up, and never seemed to reach max RMP.
Am I doing something wrong?
Does OS not like 10% nitro? (all I have at the moment)
Does low end screw need to be leaned out a little?
I am begining to think I should have got another Tunder Tiger......
cause this isnt right from what I remember of OS in the past.
Definitely rich - both the high speed and the low speed needles, which isn't a bad thing when brand new.
When you have run a couple of tanks through, open the throttle fully, and slowly screw in the high speed needle. It should speed up, until you get to a point where it starts to die, then unscrew about 1/4 - 1/2 turn.
Then set the throttle to idle, and see if it's stable. If it is, open the throttle suddenly. If it splutters and finally picks up to max speed, producing a lot of smoke, the slow speed needle is too rich. If it dies immediately, it's too lean. Keep adjusting about 1/8th turn in this way until it picks up speed almost immediately.
OS engines are amazingly good at easily getting to satisfactory needles settings and sticking to them.
-David C.