Use the manual disconnect on the electric door opener. See how difficult it
is to open the door manually.
I expect you will find one side of the door starts to lift more easily
then the door cocks over and jams. The tesnsion on the cables on each side
should be even on both sides with door closed.
You can release the spring pressure and trouble shoot the door but you
had better be very careful. You will need several pieces of half inch
diameter steel rods about a foot and a half long to bar the spring hub
around.. ( Some smaller doors use 3/8 bars)
Take a felt marker and draw a line along the spring full length. When
you release the spring the line will be a helix but will tell you just how
much to re-tension when your repairs are complete.
Wind up the spring enough to take up tension then loosen the set screw on
the end of the spring hub. At this point you could break a jaw if the unit
lets go. You have to carefully bar the spring collar around releasing the
pressure slowly.
Now with the door still down set your cables running true and make sure
the set screws of the cable hub are secure. My guess is that one of the
cable hub set screws loosened off and that is why you have uneven tension.
Wind up your spring hub until the felt mark is again a visible
horizontal line. Set the spring hub set screw to the shaft and then try the
door manually. If the spring cannot lift it enough then you need to wind on
more tension.
This is a dangerous operation and you should leave it to the trained
service people if you have any doubt about doing this repair.
Randy
Randy, he has stretcher springs rather than torsion springs.....
You offer some good info, but he can't use it. (Other than the
fact that the spring tension should be equal on each side and
that the door should be lifted by hand without much straining.)
Ken.




"George" wrote in message
.. .
I can't get my garage door to open where my tools are at. It is a
wide 2.5 car door and has 2 large long springs on each side. Yes,
this is the old dangerous kind of spring that loves to snap through
boards & people when they break.

When I look at the door from the outside, there is a visible drop on
the left side which I can plainly see due to a change in paint color
from where I painted it a year back vs. newly uncovered old paint that
was previously hidden. Thus, I know one side has definitely dropped.
I look at the railing/guides and everything tooks fine. Did a cable
slip or is one of the old springs giving out? The springs look okay
and the cable is on both pulley wheels. Beyond that, I don't know
what to look for.

If I lift on the door while someone else actuates the electric door
opener, it will then open with a little help.

Any suggestions on what to check?