If your screen or storm door shuts too quickly or too slowly, adjust the closer by turning the air-adjusting screw at the end of the closer tube clockwise (slower) or counterclockwise (faster).
If the door doesn’t latch after it has closed, remove the split pin from the small bracket to disengage the closer tube. While holding the spring in position, remove the closer pin to release the closer rod. Disengage the spring’s hook from the slot of the large bracket and, turning the spring clockwise (with a wrench if needed), insert its hooked end in the neighboring slot (or the one next to it for extra force). Reinsert the closer rod in the hub and fasten with the closer pin; reconnect the small bracket to the closer tube, using the split pin.
If the snap-action latching force (quick momentum as the door begins to close) is too swift and the slamming too noisy, reduce it: disengage the split pin from the small bracket and advance the closer tube so that its second hole is in line with that of the small bracket; reinsert the pin.
Once a year lubricate the working surfaces of the large bracket and the closer rod with lithium grease.