Do you have a rpm tester(mechanical or electronic)? 4500rpm
And I set the pressure to 18bar, that's plenty of power to dig loose soil with 14mm pistons & the 42lbs model won't move.
And no mix on the valves with the pump, just turn the pump on & leave it to run one constant speed.
Caterpillar controls are bass ackwards, JD controls are best.