What a Properly Done Spring Replacement Looks Like, Step by Step

Published August 20, 2026

Two vans can replace the same broken torsion spring on the same door. One is packed up and gone in forty minutes. The other takes closer to two hours. Both doors go up and down when the owner tries them, both invoices say the same thing, and the cheaper one is often the fast one.

The difference between those two jobs does not appear on the day. It appears about six months later, in ways that nobody traces back to the repair.

This is the long version of what the slower van was doing.

Step One: Find Out What the Door Weighs

Everything downstream depends on this number, and it is the step most often skipped, because guessing is quick and being wrong is invisible for a while.

A torsion spring is specified by wire diameter, inside diameter, length and hand of wind. Those four values, combined with the diameter of the cable drums, determine exactly how much lift the spring provides per turn. The right combination is the one that produces lift equal to the weight of your door. Not approximately equal. Equal.

Two doors on identical openings can be a long way apart. A plain single layer steel door on an older tract house near Adams Ave might weigh a hundred and thirty pounds. Swap in a three layer insulated door with a row of glazing and a carriage house overlay and you can be over two hundred on the same frame. Nothing about the opening tells you which one you are dealing with.

The honest way to find out is a scale under the door with the springs unwound. Where that is impractical, the weight can be calculated from panel construction, gauge, glazing and track type, and then confirmed by the balance test at the end. Either method is fine. What is not fine is reaching for whichever pair of springs happens to be in the van because they fit the shaft.

Step Two: Replace the Pair, Not the One That Broke

On a two spring system, both springs have completed the same number of cycles, carrying the same load, in the same coastal air, for the same number of years. One of them has just failed. The second one is not in a different situation. It is a few months behind.

There is a mechanical argument as well as a probability one. A new spring and a fatigued spring do not produce the same torque, so the shaft gets twisted harder at one end than the other. The door goes up very slightly out of square, one cable carries more than its share, and the bearings wear unevenly. You have paid for a repair and received an imbalance.

Anyone is entitled to decline the second spring, and it is not an unreasonable choice on a rarely used door. It should be a decision the homeowner makes out loud, though, not one the van makes silently to keep the quote low.

Step Three: Wind It, Then Correct It

Turns are calculated from the height of the door, and a common starting point is four quarter turns per foot of travel. That gets you close.

Close is not the same as right. A quarter turn either way is a genuine, feelable difference in how the door behaves, and the only way to find the correct number is to put the door through it and watch what happens. A technician who winds to the formula and packs up has completed the arithmetic, not the job.

While the shaft is still accessible, the cable drums get attention too. They must sit square, be seated properly on the shaft, and be set so that both cables wind on at the same rate. If one drum is a fraction out, the door will sit slightly crooked at the floor and one cable will spend its whole life carrying more than the other.

Step Four: The Parts Nobody Wants to Come Back For

The torsion shaft is only ever accessible with the springs unwound. Once the new springs are wound, going back in means unwinding them again, which is another visit and another bill.

So this is the moment for the small stuff:

• End bearings and the centre bearing plate. Inexpensive, they genuinely wear, and a dry or pitted bearing is the single most common reason a door is noisier after a spring repair than before it. Fitting new ones adds a few dollars in parts and a few minutes in labour.
• Cables, inspected along their full length. Near the water in Huntington Beach, salt works between the strands and corrodes a cable from the inside outward. Rust weeping out from between strands means it is well along, whatever the outside looks like.
• Bottom brackets. These are under full spring tension. Cracks and elongated bolt holes are a real safety item and cost almost nothing to catch now.

Step Five: Lift It by Hand Before Touching the Opener

This is the step that separates the two vans, and it takes thirty seconds.

Opener still disconnected. Lift the door by hand. It should feel like eight to ten pounds all the way, not fifty. Stop it at waist height. Let go.

A correctly set door stays there, or drifts an inch or two. If it sinks to the floor, it is under sprung. If it climbs, it is over sprung, which is less common and just as wrong. Either way the answer is to go back to the winding cone and change the number, not to reconnect the opener and let the motor cover the shortfall.

Any homeowner can run this test themselves, tonight, on a door that was repaired last year. That is rather the point of describing it.

Step Six: Reset the Opener to the New Springs

The opener learned its settings against the old springs, and in the weeks before those springs failed it was probably compensating for them. Every one of those settings is now wrong.

Up and down force get reset to the minimum that reliably moves the door, so that the opener reverses off an obstruction instead of driving through it. The down travel limit is set so the bottom seal compresses and no further, because a limit set too deep keeps the motor pushing after the door has landed, slackening the cables at the drums and letting them jump the grooves. The up limit stops the top section short of the header.

Then the safety checks that UL 325 exists for. A length of timber laid flat on the floor under the door, to confirm it reverses on contact. The photo eye beam broken mid travel, to confirm it reverses again. Sensors realigned if the indicator lights are not steady.

If the opener is being replaced rather than serviced, California SB-969 has required battery backup on newly installed residential openers since July 2019.

Six Months Later, the Rushed Version

None of the skipped steps announce themselves. Here is how they surface instead.

The door drifts. You stop it halfway to get the bikes out and it settles slowly to the floor. Everyone assumes doors do that. Properly balanced ones do not.

The opener sounds like it is working. Because it is. Every foot of every cycle, it is supplying lift the spring should have been supplying. Gears and sprockets wear on a schedule that has nothing to do with the number of times the door has been used and everything to do with how hard each cycle was.

A cable frays early. Uneven drum setting put more tension on one side from day one. Add coastal salt getting between the strands and a cable that should have gone a decade starts showing whiskers near the drum in two or three years.

The door thumps at the floor. A travel limit set too deep, or a balance that lets the last foot run away.

The new spring fails early. An undersized spring is working outside the load range its cycle rating was counted at. The cycle rating on the box was never a promise about your door.

Not one of those looks like the repair. They look like an old door, or a cheap opener, or bad luck.

What a Workmanship Guarantee Actually Promises

These two things get used interchangeably in advertising and they are not the same at all.

A parts warranty is the manufacturer’s. It covers the metal. If a spring rated for a given number of cycles fractures well inside that count, under normal use, the maker replaces the spring. What it does not cover is a spring that was never right for the door, because that is not a defect in the metal. It is a defect in the specification, and the specification was not the manufacturer’s decision. This is exactly why long parts warranties are easy to advertise and hard to claim on.

A workmanship guarantee is ours, and it covers everything the manufacturer’s warranty cannot reach: the sizing, the number of turns, the balance the door was left in, the drum seating, the cable tension, the bearing fit, the opener settings. If the door drifts, pulls crooked, thumps down, or the spring loosens because of the way we set it up, that is our problem to come back and fix, without a bill.

The reason a workmanship guarantee is worth more than a longer parts warranty is simple. Nearly every early spring failure we are called out to is a fitting problem wearing a parts problem’s clothes.

If you want to know which kind of job you got last time, go and pull the release cord, lift the door to waist height and let go. Then call (714) 987-8780 and tell us what it did.