How do you tension a garage door cable?

What is a garage door cable?

A garage door cable is a steel cable that connects the garage door to the counterbalance spring system. This spring system provides the lifting power that enables you to easily open and close the garage door.

The cables run from the bottom corners of the garage door, through a pulley on each side, and attach to the spring system which is mounted above the door opening. When the garage door opens, the cables wind around the pulley to lift the door via the spring tension. When closing, the weight of the door causes the cables to unwind from the pulleys which allows the springs to contract and lower the door.

Over time, these cables can stretch and lose tension. This results in a sagging garage door that will not open or close properly. Tension must be adjusted in the cables periodically to keep the door operating smoothly.

Why do garage door cables lose tension?

There are a few reasons why garage door cables lose proper tension over time:

• Normal wear and tear. The cables are under constant tension and will naturally stretch and fatigue over years of use.
• Damage or kinks in the cable. Kinks can occur if the cable rubs against the pulley improperly or is forced out of its track. This damages the steel wire strands and creates weak spots.
• Spring recoil issues. Improper spring winding or broken springs will cause excessive slack in the cables.
• Minor track misalignment. Any misalignment in the pulley tracks can put extra tension on the cables and cause early wear.
• Corrosion. Moisture can corrode the steel cables over time resulting in breakage.

Catching and fixing slack cables as soon as you notice a problem is key to preventing further garage door damage and avoiding a major repair.

How can you tell if your garage door cables need tensioning?

Here are the telltale signs that the cables on your garage door have lost the proper tension and need adjusting:

• The door becomes difficult to open or close.
• You have to pull down hard on the emergency release handle for the door to close.
• The garage door starts closing unevenly from one side.
• There is a sag in the cables above the garage door when closed.
• You hear loud grinding or popping noises when opening the door.
• The door will only open part of the way then reverses or stops.
• The cables are fraying or kinked.

Any of these signs indicate it’s time to tension or possibly replace the cables to restore proper operation. Ignoring sagging cables will result in escalating problems and safety issues.

How to tension a garage door cable

Tensioning the cables on your garage door is not difficult. But extreme caution must be taken as garage doors are under high spring tension and can cause serious injury if handled improperly. Follow these safe steps to properly tension the cables:

1. Start with door fully closed. Disable automatic garage door openers by unplugging the unit or disengaging the opener arm from the door.
2. exam first. Look for frayed spots or kinked areas which will require cable replacement, not re-tensioning. Also check for any signs of pulley misalignment.
3. Loosen the cable adjustment nuts and turnbuckles at the bottom of the cables on both sides. This relieves tension on the cables.
4. Examine the spring system. Check for broken springs or signs of system failure. Broken springs must be replaced.
5. Determine if one or both cables need tensioning. Grip cables firmly by hand about 6 inches above the bottom pulley. Have a helper try manually lifting the door about halfway up. Compare cable tension side to side.
6. To increase tension, turn the turnbuckle on each cable clockwise as needed. Turnbuckles are located at the cable ends. Tighten each side incrementally and recheck tension.
7. Once balanced tension is achieved with door halfway open, perform a complete open and close test. Adjust further if needed.
8. When proper tension is reached, retighten cable lock nuts to 30 ft-lbs of torque.
9. Lubricate pulleys and check door balance. Make any final spring adjustments per manufacturer specifications if door does not operate smoothly.

Proper cable tension should now be restored. The door will open smoothly and close without needing to pull down hard on the release handle.

Remember to disconnect automatic openers before performing any garage door maintenance. Have a professional garage door technician make any major repairs. Neglecting cables or using improper tension risks serious damage and hazardous door failures.

When to call a professional for garage door cable repair

Though tensioning cables is a routine DIY task, there are times it is best to call in a professional garage door repair technician:

• You notice frayed or broken cables.
• The door jams and cables jump off the pulley, become unthreaded, or break.
• You find excessive corrosion on the cables.
• Re-tensioning does not improve door operation.
• You hear loud popping noises from the springs.
• There are signs of pulley misalignment or off-tracking.
• You do not feel comfortable working with the tensioned parts.

Garage door technicians have specialized tools and expertise to thoroughly inspect system components and make all necessary repairs for smooth, long-lasting operation and safety.

Garage door cable replacement

If a garage door cable is frayed or broken, a new cable will need to be installed. Cables require very precise installation to avoid future problems:

• Buy the correct replacement cable based on garage door make and model.
• Carefully install so cable feeds properly through pulleys with no slack or kinks.
• Attach cable ends securely to their termination points. Failure risks serious injury.
• Adjust spring tension very slowly and carefully.
• Test thoroughly and re-adjust tension until door operates easily through full travel.

Due to the need for controlled spring tension adjustments, replacing broken or off-track cables is a challenging DIY job best left to qualified professionals. They have the expertise to safely switch out cables, re-set spring tension, and confirm proper door balance.

Conclusion

Garage door cables undergo extreme wear and tension over years of daily use. It’s important to periodically inspect cables and watch for signs they may need adjustment or replacement. Re-tensioning loose cables can quickly get your garage door working properly again. But at the first sign of fraying or broken cables, call a professional for repair. They have the tools and knowledge to get your door cables safely realigned and restored to smooth operation. With proper maintenance and care, your garage door cables should deliver decades of reliable service.