How To Adjust Door Closer Arm. Start with no more than 1/8 of a turn. The most common door closer adjustments are:
A mechanism of a door closer provides gradual closing of the door automatically. Now, instead of slamming shut, the door will slow down as it nears the door catch. At about 75 degrees, the door should start to slow down so that it does not slam into the surface behind or get caught by the wind.
Open the door and watch it close.
If it closes right the first time, check it 10 more times. The other adjustments we see on door closers are back check, power, and delayed action. Different applications of door closers (e.g. If it closes correctly every time, you’re done.