CHARLOTTE GUIDE

A cable is slack, or a roller is no longer round

One side of the door sits lower, a thin cable has a bright broken strand, or a roller squeals and shows a flat spot. Those parts are small compared with the door, and they carry the door. Stand to the side. Cables under tension are not a homeowner repair, and a roller that is halfway out of the track is not a part you pinch back in with your fingers.

By Mike Maziarz · Sources checked October 6, 2026 · How we write these guides

What the cables are carrying

On a torsion system the cables wind onto drums at the ends of the shaft and attach to brackets at the bottom corners of the door. When the spring turns the shaft, the cables shorten and lift. Extension-spring doors use a different path, often with pulleys along the horizontal tracks, and the same rule: the cable is loaded. A cable that looks slack may still be attached to hardware that can jump.

Do not grab a cable, do not try to wind it back onto a drum, and do not unbolt a bottom bracket. Do not wind or unwind the spring to give the cable slack. That is the injury. If strands are broken, if the cable is off the drum, or if a bracket is bent, unplug the opener and keep the opening clear. Say left or right. The side matters because the other cable may be holding alone.

Fray, rust, and a side that dropped

Humid summers leave rust on hardware that lives in an unconditioned garage. Rust and broken strands mean the cable is done, not that it needs a spray. A cable that has unwound from the drum lets that corner drop. The door then racks, which is how rollers leave the track and how a bottom section twists. You may notice the gap at the floor is wider on one side. Measure it with your eyes only.

A door that suddenly will not close evenly, or that reverses because it is hitting the jamb crooked, can be a cable story rather than a sensor story. The will not close page covers the beam and the floor. Use it to avoid blaming the eyes when one corner is already hanging. If the door is open and a cable lets go, it can become stuck open or it can fall. Either result is a reason to stay out from underneath.

Rollers that flattened or jumped

Rollers are the wheels at each hinge and at the bottom bracket. They should be round and seated in the track. A flat spot clicks once per turn. A cracked nylon tire wobbles. A steel roller on an older single door can be noisy for years and still be round. Noise alone is the noisy door conversation. A roller whose stem is bent, or whose wheel is outside the track, is this page.

Do not grease a jumped roller and push. The track may be spread or kinked, and the push loads the cable and spring at an angle. Debris from a clay driveway sticks to rollers more than people expect. Wiping a seated roller you can reach with the door down is as far as cleaning goes. If you must cross in front of the door to reach the other side, do it only while the door is fully down and the opener is idle.

Separate this from the photo eyes

Photo eyes do not lift a corner and they do not fray a cable. If the door is crooked and a cable is slack, cleaning lenses will not level it. The sensor checks matter when the door is square and still reverses. Say which fault you see so the visit brings cable hardware rather than a bracket adjustment on the eyes. Both can be true only if you actually have both symptoms. Do not raise close-force to drag a racked door down. The force setting will not reseat a drum.

Bottom brackets are part of the cable system. They are screwed into the bottom section and they are under tension when the system is wound. Loose screws in a bracket are a technician's look, not a screwdriver task while the cable is tight. If a bracket has torn out of the skin, the section may be finished as well as the cable. Describe the tear. Do not hold the corner up with a prop.

If the bad cable shows while the door is up

An open door with a slack or broken cable is unstable. Do not pull the emergency release to lower it by hand unless a person can actually hold the door. A spring that was sharing the load with a now-failed cable can let the door fall. The stuck open notes cover locking the house door and staying out of the opening. They apply even when the reason is a cable rather than a sensor.

Cars underneath should be moved only if you can do it without walking under a cocked panel. If you cannot, leave them and tell the technician a vehicle is trapped. A detached garage on a lane does not have an interior door to lock, so the exposure is the stuff inside and anyone passing the apron. Keep children out. A cable end can whip when it lets go. That is another reason to watch from the side, not from the threshold.

What a cable visit should list

Ask for cables as a pair when one has failed, and ask whether the drums are grooved or cracked. A new cable on a chewed drum will climb off again. Rollers can be replaced as a set or only where they are flat. Ask which ones they saw. Springs stay in the conversation because the technician has to unload them to do the cable safely. You are not doing that unload. Confirm they will not hand you a bar or ask you to hold tension.

Mention the house only as an address fact. A double door in Myers Park and a single door in a Wesley Heights alley use different cable lengths and the same hazard. If the work stays on cables and rollers, say so. If the track is also bent, the scope grew. Rust from humid air is a reason the metal aged. It is not a reason to grab the rusty part and tug.