RC4WD 4200xl digger questions

[KBS]

hi I try switching channel 4 and 1 I got my swing to swing on the left joystick but no bucket control what so ever?? also after running it for a while it seem like it has a lose of power on a angle maybe sometimes the arms will barely move n I shut the pump off level it out then seems ok could I be low on oil ? has anyone messed with the pump speed on these for more power. I just got the earth digger would love some tips n pointers!