To do this you will need to first detach one end of the spring from its mounting point at the back of the garage door rail farthest point away from the garage door opening.
How to install extension springs on garage door.
Then detach the lift cable from its connection point on the door rail near the garage door just above the garage opening and thread the loose cable around the sheave pulley attached to the spring.
This can still be done when only one extension spring is broken.
Torsion see above which mounts on the header above the door and extension photo 1 which floats above the upper roller track.
Tie the extension spring to the roller track then detach the cable from the bottom bracket with a pair of pliers.
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How to replace a garage door extension spring.
Granted garage door spring installation work requires time and attention so it is best to save the task for the afternoon of a free day.
Replacing garage door extension springs is not a difficult task provided you know all the key steps.
Garage doors operating with torsion springs require a minimum of 9 1 2 inches of headroom while doors using extension springs require a minimum of 4 1 2 inches of headroom.
You may need to use a 2x4 or some other object to pry the garage door open.
Garage door springs come in two styles.
Weigh your garage door.
Place scale under the garage door on the side of the door with the broken extension spring.
It is possible to mount torsion springs in a garage with only 5 inches of headroom.