How-To Adjust An Unloader Valve

Screw Unloader valve in to an approximate point where needle of the valve contacts the pump unloader pin.
Attempt to blow air through the Unloader valve while turning the valve one round at a time.
When you are able to blow air through the valve. Turn it in one more round and lock it down with the lock nut.

The pump unloader pin should retract when the pump starts up.

It is normal for an air flutter to vent from the unloader valve while running. This is the action of the pistons going up and down.

The pump must be turning clockwise when facing the sight glass.