Before beginning any project ensure that you have all the materials necessary to complete the job.
The size of the door will determine the cable size, for example a 7ft door you will use an 8’6” cable. Sizes of the tools used for this project may also vary in size, have various sizes available.
You will need vice grip or locking pliers, replacement cables, winding bars, wrenches, sockets, ratchet stepping ladder, gloves, and safety glasses. No loose fitting clothes or jewelry should be worn, proper foot wear like work boots, gloves and safety glasses are all recommended to be worn at all times.
Beware of pointed edges and small frays on cables to avoid injury.
To begin unplug and you must disengage the garage door opener by pulling on the emergency release handle this should be a red rope with handle that is located near the opener or the top rail depending on your opener . By doing so this allows you to open and close the door manually.
Open up the door and use a vice grip just below the bottom roller on both sides to hold the door open while you change the cables.
Go to the center of your door and loosen the sets screws on the springs with 1/4 turns. Remember to fully insert winding bars and use both bars at the same time to prevent injury. Do not get in the way of the bars.
Continue to unwind the spring until all of the tension has been removed, if your door has two springs do the same with the second spring
After all of the tension has been removed from springs take your wrench and begin to loosen set screws on cable drum at the top left of the door, then remove cable from cable drum. Towards the bottom the of the door take your ratchet and socket of appropriate size and remove the bottom lag screw from the jamb bracket. Remove bottom bracket, then remove the cable from the bracket.
Install new cable onto bottom bracket, thread this cable up to the cable drum at the top of the door. Remember to do this for both sides of doors.
Insert cable into the slot of the cable drum, make sure that the cable is property set and not overlapping. Wind cable onto cable drum and slide the cable drum over to the bearing plate and turn the drum counterclockwise direction until the cable is tight, now tighten the set screws. Do not over tighten.
While holding the cable use your vice grip pliers on the metal rod that goes across entire door against the wall to hold it in place and go onto the right side of the door and follow the same steps. After these steps have been completed you can now increase the tension on the springs using your winding bars remembering to only increase tension at ¼ turns at a time to not over wind springs.
Remove locking pliers from metal rod at the top of the door, re-engage door by pulling down emergency release and lifting door until you hear it double click into place and plug opener back in.
It is impossible to predict all repair circumstances. These steps must be followed in order to prevent any damage to your door and or person.