It is entirely possible to stop, refactor, be a little behind on features, slam in a few features, not catch up but screw up the code, and loop forever, never getting benefit.

Screw pump should be in suction stop valve fully open under the condition of starting, in case of overload or empty.

If the operator mounting holes do not line up with the valve flange holes, the stop screw (s) should be backed off and handwheel turned until holes are aligned.