Install the new spring reinstall the pulley and reconnect the safety cable and you re done.
How to install garage door spring.
In the past extension springs were safer to install but didn t have containment cables running through the center of the spring.
Open the door to relieve the spring tension and secure it open with c clamps in the tracks.
A couple of carabiners can.
Torsion see above which mounts on the header above the door and extension photo 1 which floats above the upper roller track.
Disconnect the spring from the track bracket and the spring pulley and disconnect the safety cable from one end.
A pair of new springs cost about 25.
The general process is simple and safe.