HOME IMPROVEMENT : HANDYMAN Q & A : Garage Door Glides on Proper Spring Tension

QUESTION: My garage door has become very hard to raise and lower. Would you please explain the mechanics of overhead garage door springs and their adjustment? Do I need any new springs or other parts?

ANSWER: The door’s springs help you overcome its weight when you raise it. They also keep the door from crashing to the floor when you lower it. Without these springs, it would take a very strong person to operate the door. When correctly tensioned, these springs should make it easy and safe for even a child to open and close the door.

There are two types of garage door springs. One type has two springs that are located near and parallel to the tracks the door runs on when raised. The other is a single spring across the top of the door that winds up somewhat like the spring in a window shade.

You adjust the parallel spring by changing the length of the wire cable where it is attached to the frame of the garage. The cable runs through the pulleys to the attachment on the door. It may be secured by a knot or a clamp where it passes through this retaining plate.

Before you adjust spring tension, raise the door to its highest position and prop it securely with a length of 2 by 4. This reduces spring tension to the minimum and prevents the door from dropping to the floor if you lose control of the spring while shortening the cable. Use extreme caution when adjusting spring tension and wear safety goggles and gloves. Have a helper standing by if possible.

To adjust the coiled roller type of spring mounted over the door, lock the door in the down position. Firmly attach a pair of vise grips to the spring shaft and wedge the vise grips handle firmly against the garage door header. This step is extremely important. Use two bars that fit in the adjusting holes of the winding cone. If the door comes down hard, you’ll need to increase the tension on the spring. If the door tends to lift off the floor, you’ll need to decrease spring tension.

To adjust the spring tension, insert one bar in the winding cone, in the hole closest to you, and rotate the spring one-quarter turn to increase or decrease tension as necessary. Hold the bar in this position while inserting the second bar in the winding cone to further adjust the spring tension if necessary.

Never pull the first winding bar out of the cone until the second bar is inserted securely. Be sure all the set screws on the winding cone are tightened before you remove both winding bars, and don’t forget to remove the vise grips before operating the door.

For further information on any home problem, write to Popular Mechanics, Readers Service Bureau, 224 West 57th Street, New York, N.Y. 10019.