Center and level the first section after you install the brackets. The door must be level even if the floor isn’t, so use shims under the section to level it. The rubber gasket on the bottom section will fill the gaps created by an unlevel floor. To hold the level in place, tape it to the section. To hold the section in place, lightly toenail a 16d nail into the frame and bend it over the section. Add brackets and rollers before setting them in place and stack one section on top of another, toenailing as you go up.
You might genuinely need some extra parts when you thought you simply needed a broken spring replaced, and a good serviceman will perform a simple inspection to identify such parts. Nor is it unreasonable for a business to charge separately for a service call versus repair work actually performed. But the best protection for you as a buyer, being somewhat at the mercy of whomever you decide to bring on site, is to understand what is being done, and ask intelligently for a clear explanation or demonstration of why extra parts are required.
Garage Door Opener Company
The two set-screws in the winding cones have a 3/8-inch square head, which fits a 3/8-inch open-end wrench or 8-point socket, or a 7/16-inch 12-point socket or 12-point closed-end wrench. I carried an extra wrench in my pocket while winding, since I didn't want to be holding a wound spring that I couldn't set because I had dropped the wrench (although one could rest the winding rod against the door in this case while picking up a dropped tool).
If your garage door is opening slowly or making a lot of noise, the problem may not be your opener. So before you buy a new one, check for broken or wobbly rollers and brackets. But don’t replace the bottom roller bracket yourself—the cable attached to it is under extreme tension. You’ll need to call a pro. If you’re replacing the rollers, get nylon rollers. They operate quieter than steel rollers and cost only a few bucks more. Next, check the torsion spring (mounted on the header above the door opening) to see if it’s broken. When one breaks, you’ll see a gap in the coils. You’ll need a pro to replace a broken spring.