Garage door spring – Many single car garage doors with extension springs lift the door weight when you open or close the garage door. An extension spring is usually on each side of the door above the upper door track. A little wider garage doors use two extension springs on each side, but these are not common. The springs connect to the rear track holding brackets. Door cable passes over a pulley and tracks through a pulley near the front in the spring. A garage door extension spring adjustment is a matter of moving the door cable.
Fully open garage door spring. Attach a pair of vise grips in the curve of the door track, with handles on the vise-grip under the roller at the bottom of each side of the door. The weight of the door will rest on the handles of the vise-grip. The power cord garage door opener, for your door using the opener. Setting up a ladder in the opener motor and pull the opener power cord from the ceiling outlet.
Place the ladder on the right side of the door between the wall and the front of the extension garage door spring. Search adjustment holes on the course. Upper groove connecting to the vertical groove with a straight bracket. The connecting bracket has several holes on the top. The end of the cable attaches to these adjustment holes for the cutting and the S-hook. Search for the lower part of the door of the cable where it comes under the pulley on the front of the spring. Grasp the lower part of the cable with one hand and pull it against the wall just enough to give slack on the S-hook and cut.