The garage door cable is an essential part of your garage door system. If you discover a problem involving the cable, you will need to perform the repairs or contact a garage door repair service for help. If the cable is broken, contact a repair company to fix it. If you are considering fixing it yourself, please first read this disclaimer and then the tips below:
Disclaimer: This information is not intended to be understood as an official guide and will be provided for informational purposes, only. There is danger involved in garage door repairs, especially with repairing broken garage door cables. All garage door repairs should be performed by a professional. My Garage Door is not to be held responsible for any repairs undertaken by any licensed or non-licensed individual following the information provided here.
What is the purpose of garage door cables?
The garage door cables are the most crucial part of the whole system. It is held under tension by the spring and attached to the drums and bottom bracket plates. These cables attach both garage doors to the cable drum at either end of the torsion or extension spring shaft.
Whenever the torsion spring turns, the drums will wrap or unwrap the cable. This causes the lifting or closing of the doors. If one of the cables breaks, all of the pressure will transfer to the remaining cable. From this point, the remaining cable will fail, the door won’t operate properly and it’s a dangerous situation. It will put high pressure on the other cable, roller, or tracks, your door will not be properly aligned, and the closing/opening will also be a difficult task to perform. The additional pressure causes the cable to come off the garage door.
Garage door cables can come off track for a number of reasons. For your door to work properly, there needs to be just the right amount of tension between the cables and the springs, and if that balance is upset, the cable can come unwound. This could be because the torsion spring is broken, the drum is the wrong size for the spring, or maybe even because the door hit an object.
If one of the cables has broken or come off track, it is possible to replace or realign it in a short amount of time, if the proper caution is taken. First, if you have an automatic garage door opener, disconnect he power plug from the opener to prevent any electrical accidents while you are working. Open the door all the way and use clamps on the tracks to hold the door open while you repair the cable.
Before attempting to remove the broken cable, it is essential to release the tension in the garage door torsion springs. These springs are under extreme amounts of tension. It is dangerous to attempt to remove the cable without releasing the tension in the springs, as it can cause the springs to recoil suddenly and injure or even kill someone.
To proceed safely, use a vise-grip clamp to grip the shaft, and turn the shaft just enough to loosen the cable. (Not too much though – if you over-loosen the shaft, you could unwind the cable on the other side of the door, making a lot more work for you). You can now detach the old cable from the pin at bottom of the garage door. Slowly unwind the cable and remove it entirely from the drum.
For a garage door that is 7 feet high, you will need a new cable that is 8 feet 6 inches long and for a door that’s 8 feet high, you need one that’s 9 feet and 6 inches long. On one end of the cable there will be a tip which will fit neatly inside the drum; the other end has a loop to attach to the nipple on the bottom bracket plates attached to the bottom section of the garage door. At this point, you can easily slide the tip into its slot in the cable drum, and tightly wrap the cable around the drum. Keep your hand on the cable at all times and wind it neatly until you can attach the loop at the other end to the pin at the bottom of your garage door. When it is attached, use your vise-grip once again to turn the shaft and tighten the cable around the drum one last time. Be sure not to over-tighten the drum!
After replacing the broken cable, you should check the drum and cable on the other side of the door to make sure it hasn’t come unwrapped while you were working. If both sets of cables are properly aligned, you can now remove the clamps from the garage tracks and gently lower the door by hand.