Automatic doors require not only the installation of a heavy door, but the motor and cables as well. Automatic doors are much more common now because of their convenience, but in a case such as the heavy wood door, they are a necessity. A strong motor is required to pull up a heavy door. However, automatic doors are not without their faults -- they quickly become a manual door when the power goes out.
In addition to the bodily risk involved, it’s simply not an easy task. There’s the possibility that you will not install it correctly. At worst, this creates the risk that the mechanism will fail at the wrong time and injure you or someone in your family. At best, this means it will malfunction, and you’ll have to call professionals to fix it. It will save time, money and potential heartache to simply call a professional to install your new door springs correctly the first time.
9.9 Go to the other side of the garage door and insert the end of the cable into the drum. Rotate the drum until the cable is tight. Slide the drum against the bearing and push the shaft to the right. The marks should line up. If they don't, figure out why and correct the problem. It could be a stuck cable, the garage floor may have shifted, or the vertical angle that helps support the bearing plate may have loosened and shifted. Many garage doors have been installed with a gap between a drum and a bearing plate. The cable drums should always be flush against the race of the bearings.