another valve question

[cosworth34677]

hey i got a problem with my excavator . my mangom valves seem to work great. but the servos act like there is not enough throw to open the valve fully in the retract direction, i have tried to cent er servo with the trim and by taking off the servo horn but it seems nothing is working to get the center in the right place to have even movement in both directions?

so being me, i was wondering if there is a trick to this setup? i mean when the boom goes up its at full power and crazy strong but when it goes down its slow and have less then half power. what im wondering if there is something in the valve clogging them ? but if i take the servo off and move the valve by hand it works fine, but when put the servo on it back to the problem. i even went and got a new set of servo's today the stick and bucket work great its just the boom. what of any idea's can help me?

[Espeefan]

If the valves are working fine, by hand, then maybe it's a radio programming issue. Double check your servo end points. Maybe you accidently decreased the end point in the direction you say the valves don't seem to be opening all the way? If you don't have a programmable radio, then that probably won't help.

If you do have a programmable radio, center the servos, with the horns on the shafts by adjusting the sub-trim. Then adjust the end points, which will control how much travel the servo has to the left and right. Sub-trim is not the same as your adjustment trim. Sub-trim will in effect set a new center point, or neutral point, for each servo individually. Use it when you can't quite seem to get the servo horn centered up on the shaft. The splines might get you close, when you take the horn off, and try to turn it one spline left, or right, but often times it wouldn't be perfect. That's where sub-trim comes into play.