Whether your problem is the working table stop at single side i.e.: left side or right side.
Our engineer said that there might be some deflection of the center line of direction control shaft or direction control arm.
Please take apart the screws of direction control arm, then separate the direction control arm and direction control shaft.
We supposed that the position of shaft or arm is a little deflection, kindly turn/ adjust both shaft and cam slowly to inspect the improvement.
In addition, thank you for your confirmation to keep the hydraulic valve as stock and we will inform upon receipt the payment from your end.
Please feel free to contact us if you have any problem.