Re: garage door adjustment
These problems are usually caused by a slight misadjustment of the large springs on either side of the door or a slight track misalignment.
Sometimes grease & lubricants on the rollers inside the steel tracks cakes up/solidifies (especially in cold weather) & causes rough door movement.
The rollers can usually be cleaned in place by closing the door, placing an old rag at the base of each steel track & dousing all the rollers inside the track with plenty of spray penetrating oil or WD-40---an old toothbrush can then be used to remove any caked-on grease.
The roller bearings can be individually removed if one refuses to move, or squeaks, even when lubricated, by removing the bracket screws on the door bracket & removing the individual roller bearing for individual testing or replacement---the roller bearing should rotate smoothly in your hand with no roughness--replacements are low-cost & widely available.
There are several types of garage doors with various types of spring arrangements---some have a large powerful torsion spring directly above the door---these should be left to a pro, as personal injury can occur if you try to service these.
If you are talking about the standard non-torsion spring garage door---with a large spring on either side of the door--driven by an electric motor opener---the main diy procedure is to detach the electric opener from the door with the emergency pull handle---and work the door manually---open & close it several times to get the feel of any mis-alignment---if it works smoothly in manual mode--it will work smoothly in electric, automatic mode.
In the manual mode, position the door at "half-open" & let go of the handle--the door should remain where you left it and not creep up or down on its own.
If it creeps down, one or both the springs are too loose & must be tightened.
Position the door at various points in the open/close sequence & let go---look closely--you may see one of the springs pull the door to one side at the edge---meaning the other spring should be tightened to equalize the two spring tensions.
Use a long 2 X 4 piece of lumber to jamb the door open---this will take the tension off the springs & prevent the door from closing when you un-knot the thin cable holding the spring---you can then adjust the springs so they are of equal tension--this is the usual cause of sloppy closings; if you have a "vise-grip" pliers--you can also attach this to the steel track at the base of the open door to prevent door movement---if you have one or two large adjustable C-clamps you can install these tightly on the steel track at the base of the open door, to prevent door movement.
Look closely at the tracks & the brackets securing the tracks & brackets to the door jamb to make sure none of them have worked loose & are out of slight alignment---this is the 2nd most likely cause of jerky door operation; tighten any loose bolts that hold the brackets/tracks to the garage wall/jamb & ceiling, especially along the jambs & near the base of the door.
Take a steel ruler that can extend at least 8 to 10 feet & measure the distance between the vertical steel track on the left side of the door to the vertical steel track on the right side of the door---the tracks should be equidistant from each other (give or take 1/2"); measure at the base of the door & continue all the way to the top of the tracks-- if there is any variation, loosen the bolt brackets & get the tracks equidistant to each other.
Take a spirit level & see if the steel tracks on either side of the door are plumb (vertical)--adjust if not, as above.
Lubricants such as silicon sprays will ease the binding in some cases & "cure" the problem, but make sure the tracks are aligned & tight as well for a permanent repair.
Some of the sites below have diagrams on how to adjust the springs---a simple matter once the door is jammed open with the long 2 X 4----the little steel cables that control the spring's tension by a small steel wheel sheave are in a KNOT at the side of the door on the horizontal piece of the upper portion of the flag bracket at just above eye level---loosening & tightening the knot will add a little more tension to a loose spring as it closes--the knot is then tightened onto the short horizontal piece labeled the horizontal bracket in the steelbuilding site below; see also the first site for the location of the KNOT.
The steelbuilding site has a diagram showing the "flag bracket"---the cable attached to the spring is connected either directly in a knot to the flag bracket, or to a little bracket attached to the flag bracket.
Do not remove the 2 X 4 or the vise grip tool propping the door open until you are sure you have the large springs on either side of the door attached to the door in the open position.
Many of the large home improvement books at the public library have much more elaborate diagrams and photos of garage door parts and components---look in the 643.7 numbering system area of the library stacks.
Re: garage door adjustment
I did not see any statement, if you are using a electric door opener. If so there are two screws that adjust upper limit and lower limit, on most openers. The Stanley screw drive has two limit switches on the top of the screw drive rail.