Garage door loose cable

[billkater]

Hello all....

I am having a problem with my new garage door. The cable on the left hand side gets loose when door is completely open. This messes with the Chamberlain Jack Shaft opener. There is a sensor on the cable to detect a loose one. I have worked on it over and over and can not figure out what is wrong.

It has a torsion spring. I have done the following to trouble shoot:

1. Verified door level when down.
2. Verified both springs wound the same (rewound them 3 or 4 times)
3. Verified cable pickup wheels both set correctly. (cable tight on both cables when door down.
4. Verified door is free and doesn't drag when moving.

This is a brand new door and opener. This is a brand new building. I have installed 5 doors (4 in side wall, 1 in end wall). This is the only door that is causing me problems.

I am at a loss. Cant seem to figure it out. Any suggestions?

I have a video of the cable on YouTube. But not allowed to post a direct link to it.


And photos below.

The last photo shows the cable on the sensor with door in up position. The other picture of the cable is the other side of the door.

 

[matt_i]

It sounds like the free cable isn't taken up correctly.

Loosen the springs. Get one side's cable taut (door fully down) by hand tension on the sheave for that side. Place visegrip against inner upper wall of garage to hold the rotational position of the driveshaft. Goto the other side and with that sheave loose, tension the cable, again by hand. While holding position, lock that sheave to the driveshaft.

Now remove the vise grip and tension both springs.

All should be equal.

 

[billkater]

Loosen the springs. Get one side's cable taut (door fully down) by hand tension on the sheave for that side. Place visegrip against inner upper wall of garage to hold the rotational position of the driveshaft. Goto the other side and with that sheave loose, tension the cable, again by hand. While holding position, lock that sheave to the driveshaft.

Now remove the vise grip and tension both springs.

I have done this twice. Doing one side first. Next time starting with the other.

I used vise grips and a tarp strap to hold tension on first sheave while adjusting the other. Same way I did all the other doors. No change in the way it functions. Still getting slack at full open.



Thanks for the suggestion

 

[The Cobbler]

could the door be not opening parallel? if it's cocked to one side ???

 

[billkater]

could the door be not opening parallel? if it's cocked to one side ???

It don't look like it. Slack on the sides between door and track when full up. But I will square it and see what I find

 

[matt_i]

Have you tried measuring the wire diameter with a caliper, next would be counting the free-turns or measuring the length.

If you got substituted a slightly different spring that would do it.

What if you crank the loose side 1/4 turn more on the driveshaft?

 

[The Cobbler]

you have a left & right hub too? also wondering if the hubs are mismatched by chance

 

[PassnThru]

could the door be not opening parallel? if it's cocked to one side ???

That would be my best guess. With it up measure both sides from the top of the door to the end of the track. You are binding somewhere and one side is stopping short of the other.

 

[Viper98912]

I had an installer once tell me that on a double door with a double spring and using a jackshaft opener, he would give one of the springs an extra 1/4 or 1/2 turn because of this and it'd help for the far side (compared to where the opener was mounted).

(doesn't make sense to me, but I'm not an installer)

 

[PassnThru]

First 2 panels need to be checked and adjusted for level.

Good point. If it isn't level to start with then it won't wind up correctly if the opener is adjusted to 'slam' the door down to seal all the way across. I have lateral movement in one of my doors due to the ridge in the concrete in the middle. With a normal opener, the only issue is occasionally recentering the door since it tends to drive to one side.

 

[PassnThru]

I had an installer once tell me that on a double door with a double spring and using a jackshaft opener, he would give one of the springs an extra 1/4 or 1/2 turn because of this and it'd help for the far side (compared to where the opener was mounted).

(doesn't make sense to me, but I'm not an installer)

We (or he rather) is assuming that there is a lot of torsional flex in that bar that everything is attached to. I wouldn't think that would be the case but I have been wrong before.

 

[mitusa]

Is the black thing in picture six causing the cable to differ in length.......should the cable run on the other side of the black shaft??

 

[snarkdek]

I had this happen to one of my doors and it was a bad bearing in the cable reel. It shouldn't happen with a new door but it happened to mine a few years ago.

 

[billkater]

Is the black thing in picture six causing the cable to differ in length.......should the cable run on the other side of the black shaft??

That is the sensor. If is spring loaded with a micro switch. When there is enough slack in the cable it makes the micro switch and the door stops.

 

[iamrfixit]

Confirm that the ceiling tracks are square, perfectly 90 degrees from the header as well as parallel to each other.

I'd also check that the panels remain level as the door is being opened.

Looking at the last two pics it does appear the drum and track brackets might be slightly lower on the loose cable but certainly not by very much. Maybe measure from the floor up to the center of the torsion tube on both sides just to check.

The cables both tight with the door closed and the panels level, that is confusing.

 

[fmf111]

Measure from the top of the top section to the center line of the spring shaft at both sides, I bet your off just enough to cause one cable to be slack when open.

 

[Fasthotrod]

Measure from the top of the top section to the center line of the spring shaft at both sides, I bet your off just enough to cause one cable to be slack when open.

I think you're right.

If it were me, I'd shoot a laser level across the door as a reference point, then check to see where the upper brackets and bar are relative to the laser line. Then check the tracks and the distance to the floor from the laser line. I'd bet that the right side that is still tight is a longer distance than the left, hence the slack in the cable.

If you go back and look at pictures 5 and 6 that show the right and left brackets, you can see that one has the bolts at the end of the slot, while the other is in the middle position of the slot. I'd bet that's the difference right there.

Hope this helps.

 

[Hot Rod Grampa]

It sounds like the tracks are not square to the header. Measure diagonals off end of track to opposite corner. My guess is they will not be the same. They may be parallel, but one slack cable only when open usually means not square. Both springs, drums and opener are connected to the same tube. Any force applied to the tube will be transmitted to the other parts equally. Winding one spring an extra 1/4 turn is to make sure there is a little tension on the cable when the door is fully opened. If you start building the door before leveling the first section and the track, you may also have issues. Take a measurement from the first joint between the panels to the joint in the track just before it starts to turn. They should be even. Good luck.

 

[billkater]

This is what came up with. The door is 1/4" lower on the right. The right hand side rail is 3/8" lower than the left. The jack shaft is 1/16 lower on right. The floor dives on the right also.

When installing the doors I put a 1/2 shim under the side rails to keep them off the floor. I didn't level them. That is why the side rails aren't level. I know I leveled the door. Must of been under the seal instead of the bracket when I shimmed it.

I will start from scratch, relevel door. Raise side rail. Retighten springs. And see what happens.

 

[like2wheel]

I'd bet it's more of an issue that the overhead (vertical) tracks are not square to the wall.
It's easy to screw up because there is often little to reference on the ceiling when installing them. So one starts off crooked, then you measure to the other one so they are parallel but a parrellagram.

 

[billkater]

I'd bet it's more of an issue that the overhead (vertical) tracks are not square to the wall.

I checked this. They are square to the wall using the 3 4 5 method. That was one of the first things I checked.