So I noticed the other day that the pull cables on my extension spring
garage door had fallen off of the pulleys (the ones vertically aligned
with the door when its down) on both sides.
I decided to start by replacing the cables. The pulleys all seem fine
- they turn and are not bent in any way. I did this on one side, and
I noticed the instructions sort of breezed over how tight you should
make it (ie where to secure the other end of the pull string to the
fixed position on the ceiling). I basically placed it such that, when
the door was open, the cable would remain just taunt between the
pulleys so that they would not sag.
I then took a closer look at the side which I had yet to replace. I
noticed that, when the door is fully opened, the wire sags severely
between the pulleys. There is no chance it would stay on without any
tension. Here are my questions:
1) While working, I had the garage door fully pulled up so that it was
completely flat in the opened positoin (and braced with clamps). I
can't remember for sure, but I assume that in normal operation it
never goes up that far - it must stay down a bit where the last
segment actually bends slightly. If this is the case, I think the
cable has a better chance of staying in the pullys, but right now I
don't even think my newly installed side would stay this way. So,
does the pully system rely on the door never being completely
2) Does the sagging indicate that my springs need to be replaced?
They still seem to pull up the door when the pully remains on the
track, so I assume they are OK.
3) What is the proper method for setting the tension of the pull cable
in a resting position? I'm concerned about it being too loose and
causing the cable to fall off the pulleys in the up position, or it
being too tight and causing breakage of the springs in the down
It may not "rely" on that, but I can't recall seeing an overhead
sectional door where the bottom section ended up fully horizontal when "up".
I have always adjusted the spring tension by trial and error so that the
door's weight is just balanced when the door is raised half way up, and
it'll "hang" at that position without having to hold it. If the springs
are correctly sized to the weight of the door, that should do it.
Do you have "safety cables" running through the spring bores? If you
don't, do yourself and others a favor by picking up a set and installing
them. They cost less than ten bucks and it only takes a few minutes to
hook them up. The head you save could be your own if a spring decides to
snap and flail around whilst you're standing in the wrong spot.
Safety cables will help prevent the "spring sag" you mention as well as
any flopping about which might be what's causing the cables to flop off
Thanks. Answer is yes, I do have safety cables installed. They are
very slack though. I read somewhere this was supposed to be the case
- they should not provide any tension but just hold things in place if
the springs decide to go. Are they supposed to be more taunt? This
install looks pretty sloppy, so it wouldn't suprise me if they didn't
do it correctly. Then again, I think it must have been running OK
like this for years because its fairly old. (I only moved in 6 mos
Thanks all for the suggestions. I THINK I set up the tension
correctly, but I am having other problems. I need some help
determining if they are related.
After I installed the new cables, I was able to tension them such that
the door opened and closed fairly smoothly without much effort. I
hooked up the opener and was able to open close 3 or 4 times with no
Then, I went to test it again later, and it kept getting stuck. I
tried pulling it up and down manually and noticed that it was randomly
and sticking in either direction. If I keep pushing or pulling, the
thing won't budge in these cases. However, if I let up on the
pressure, or briefly change directions, it'll usuall slide right
through whichever spot it was previously sticking on.
I don't see any obvious obstruction. The rollers all seem to roll,
and the thing is evenly in the tracks. What the heck else could it
be? The biggest difficulty here is that it seems to stick randomly,
in any given spot, going in either direction. I have to assume its
somehow related to the pull cables having falled off the tracks
earlier - seems like too much of a conincidence otherwise. Could this
be a problem with my tensioning, or some kind of damage from when the
cables were off the pulleys?
It sounds like the tension on the cables is unequal causing the door
to get cocked in the opening. The opener pulls from the center of the
door, so unequal spring tension will cause one side to go up higher
and the whole door will be sideways in the tracks.
You might also want to check the distance from the track to the
rollers on each side, you don't want a big gap - you should be able to
grab a roller stem and move it about and inch at most sliding in the
hinge. A quick fix may be to just take a hammer to the track brackets
and nudge them closer to the inside of the opening (if there is room
for adjustment), otherwise you may need to whip out the impact gun or
drill and re-set the tracks by moving the lag screws.
"Safety cables will help prevent the "spring sag" you mention as well
any flopping about which might be what's causing the cables to flop
the pulleys. "
I don't think that can be emphasized enough. I remember about 50 years
ago in the infancy of overhead doors, having one snap in my dads
garage. It tore up everything in its path, including a sturdy angle
braced 2 X 4 mount for the top end, that it broke in half. It sounded
like the house exploded
Adjust it so there is just enough tension on the springs to keep the
cables on the pulleys when the door is fully raised. You are correct
that the safety cables are there 'just in case' and should be
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.