English to Greek Tech/Engineering Mechanics / Mech Engineering

Carefully screw the actuator (with its locknut screwed back) until the spindle just contacts the valve unloader.
The unloader is spring loaded so take care to just contact it and NOT depress it.
Screw back the actuator about 1.5mm and pinch tighten the locknut.
Insert a hard wood dowel/rod through the control air connection hole in the top of the actuator casing until it just touches the top of the diaphragm.
With the dowel/rod in position, mark it accurately in line with the actuator cover plate top.
Using the dowel/rod depress the actuator (against the action of the spindle return spring) until it just contacts the unloader, but do not depress it.