Locate the adjustment screw on the door closer near the bracket that attaches the closer to the screen or storm door.
Twist the screw clockwise with a Phillips screwdriver to slow the speed at which the door closes.
Twist the screw counterclockwise to increase the speed at which the door closes.
Open the door a few inches. Slide the hold-open washer to the end of the door closer cylinder to keep the door open.
Pull the pin straight out that attaches the end of the closer to the door bracket. Move the closer to the hole in the bracket farthest away from the closer if you want the door to latch more smoothly. Note that this may be the desired position for a lightweight screen door or a storm door that has a screen installed.
Move the closer to the hole in the bracket nearest to the closer if you want the door to latch more positively. Note that this may be the desired position for a heavier door or a storm door that has the glass installed.
Replace the pin through the bracket and the hole in the end of the closer. Open the door further and slide the hold-open washer back toward the door jamb.
Open the door. Pull the pin straight out that attaches the closer rod to the bracket mounted on the door jamb. Let the rod retract into the closer cylinder.
Pull the closer rod out of the cylinder to the lugs or marks on the closer rod. Slide the hold-open washer to the end of the cylinder to keep the rod in this orientation.
Close the door until the mounting hole in the end of the closer rod aligns with the hole in the bracket on the door jamb. Push the pin back through the holes.
Keep the hold-open washer in this position, which should accelerate the door's closing the last few inches of travel, making for a positive latch.