Cable and Drum Inspection

The two lift cables carry the entire weight of the door every time it moves, and they are thin galvanised strand living in whatever water runs down the panel. A full service booked through Orange County Garage Door Tune Up, CA ageducate includes them every visit, because a cable failure on an Orange County garage door is sudden, one sided, and the fastest way to bend a rail.

Where It Fails

At the bottom bracket, almost always. The strand turns around a fitting there, sits at floor level, and takes the salt and grit that come in under the door. Breaks start on the inside of that bend and work outward, so the outside can look sound while the core has gone.

The Rag Test

With the door open and the opener disconnected, draw a folded rag slowly along the length of each cable. Broken strands catch it like fish hooks. Anything that snags means replacement, and a length that has been snagging for a while will already be missing strands at the bend where you cannot see.

Reading the Drum

Open the door halfway and look at both drums. The wrap should sit in consecutive grooves with no crossover, no loop and no visible slack. A wrap that has climbed over itself will slip suddenly and drop that corner of the door, which is exactly how a rail gets bent and a roller ends up out of its channel.

Even Tension

Close the door and look at the gap along the floor. A door sitting higher on one corner is being lifted unevenly, which comes from a drum set screw that has crept or one side stretching more than the other. Correcting it means resetting the drums against the shaft, which is a job requiring winding bars and the spring tension released first.

Always in Pairs

Both sides have done the same number of cycles and are the same age, so replacing one leaves a part with an identical history beside it that simply has not failed yet. Doing a single side is a false economy in exactly the way that changing one roller is.

What Not to Attempt

This work means the bottom bracket and the drum, and both are under torsion spring load. A homeowner can inspect, photograph and report everything on this page safely with the door closed, and should stop at the point where anything needs loosening. That boundary is the difference between a tune up and an injury.