the jib boom will go up ok but then it immediately comes down, about 1 ft/sec. not sure if seal inside cylinder is bad or counterbalance valve, or ?
the platform won't rotate either way. it did rotate some while bleeding it.
machine is 2002 but only 270hrs on it.
thank you
the jib cylinder could be leaking, move the jib up a little, then down and hold the valve in the down position for ten seconds, then immediately go and feel the cylinder, it should be warm where the piston is inside if it's leaking. If you can't feel the difference, try it again for twenty seconds, then feel the control valve also to see if that's turned warm also.
You won't learn anything new by teeing into the lines to the cylinder, disconnect the line and cap it with the gauge. It won't build pressure if the cylinder is leaking. If the valve is good, the pressure will go up to the max system pressure with the line capped.
The platform rotate not moving you could test by teeing to see what that says. Is that a hydraulic cylinder that rotates the platform?