LM 8500 movement while operating

[Hondaracer2oo4]

Just got my first of three garage doors installed. I installed the door yesterday and it operated smoothly up and down by hand. I then installed the opener lm8500. When I first operated the opener it had a lot of movement. I noticed that the jack shaft was moving side to side, the bearing plate would actually move side to side. I had at first slid te jack shaft actually inside the lm, so I loosened the collar and the mounting bracket. I slid the opener over so that the collar was only grabbing the shaft end, about 1 inch of jackstaft. Then reattached mounting bracket. This seems to have eliminated most of the opener movement but not all. It was late and dark so I didn't look at the jackstaft to see if it was moving the bearing plate in and out still. I will be able to look tomorrow at that again but my question is how much movement is ok with the lm8500 opener and how why would the jack shaft move left to right?

 

[Trey T]

your jack shaft move because your torsion bar moves as the door moves.

Do you have any photos of your drums when opened and closed?

 

[Hondaracer2oo4]

I can take pics tomorrow morning. What are you looking for with the drums? I did slide both of them all the way out to the bearing plates. I did find that you need to install the left drum first, tighten the cable taught, lock that one down and secure the jackshaft with the vice grips and then do the other side. If you do the right hand first I found that when tightening the drum bolts down to the shaft that since the bolts rotate clockwise when tightening they cause the drum to spin enough on th shaft to loosen the cable. If you do the right hand second, it actually tightens the cable slightly instead of loosening.

 

[imnutz]

When I know I'm putting on a jackshaft operator, I always order the door with two springs so that they work against each other and not the end bearing plate. A single spring with .250 wire on an 8' door will try to move the shaft sideways a little over 2"

 

[Hondaracer2oo4]

Hmm, these are single springs. I hadn't seen anything written in the lm manual about single vs dual springs. I have never installed garae doors so I had bo idea about the movement, any way to fix this other than dual springs? I will have to mark the shaft some way and see how far it's moving.

 

[justnutsandbolts]

Take vids and post.

I do not think there is a fix without the dual springs.

I also have one spring on a 8x9 door and I am having a similar issue without the opener installed. I am beginning to think this is because the spring gets shorter when the door is up and longer when the door is down, which moves the bar about 0.25 - 0.5 " since it just floating in the 3 bearings (LH, Center, RH)

This is why the vids on ddmgaragedoors.com tell you to hit the bar that you are using to wind the spring so that it neutralized its position.

On an another note, I think dual springs are a safe bet. If the spring breaks when your door is moving up/down, this opener might not be able to hold it, but the other spring will help it stay.

 

[Hondaracer2oo4]

I will take some vids and post pics, I am really surprised that liftmaster mentions nothing about single spring doors having this issue and an internet search also turned nothing up about this. What do you mean by hit winding bar to nuetralize the position? I guess I will have to watch the video. You would think te garage door dealer would have seen this before but he mentioned nothing about it when I told him my plan of using a jackshaft opener with the doors.

 

[Trey T]

Take vids and post.

I do not think there is a fix without the dual springs.

I also have one spring on a 8x9 door and I am having a similar issue without the opener installed. I am beginning to think this is because the spring gets shorter when the door is up and longer when the door is down, which moves the bar about 0.25 - 0.5 " since it just floating in the 3 bearings (LH, Center, RH)

This is why the vids on ddmgaragedoors.com tell you to hit the bar that you are using to wind the spring so that it neutralized its position.

On an another note, I think dual springs are a safe bet. If the spring breaks when your door is moving up/down, this opener might not be able to hold it, but the other spring will help it stay.

That's a good point!

 

[dbphelps]

I have two LM8500 openers that I used to replace some Genie screw-drive openers when I put my lift in.

The rod the spring and pulleys are mounted to will always try to move left-right because of the spring issue mentioned. But if you have the bearing plates mounted properly and the pulleys mounted properly it should only be allowed to move like 1/8-1/4" total left to right and lateral movement is a non-issue.

I also had a bunch of movement out of the LM8500s when I first set them up. The rod used in my setup is soft, thus teh collar was crushing it a lot and causing it to be off-center and thus the excessive movement. I ended up redoing the collar setup on both (basically rotated them 90 degrees) and then worked to make sure the rod was centered, not too crushed and made sure the set screws were really torqued down properly.

I still get s little movement on the LM8500s and I know if I went to a stiffer rod (or even a solid one) I wouldn't get any, but for as little as they move now it isn't an issue. it is WAY better than when I first put them in, and I sure as hell can't justify replacing the rods (too much of a PITA). The doors I have are very heavy (part wood insulated Stanley Ones that were sitting in a warehouse for over 20 years) and I have no interest is messing with anything now that they are setup perfect.

 

[gnpenning]

Liftmaster doesn't say anything about single-dual springs because it doesn't matter.

The second spring will not be able to support the weight of the door by it's self. It may slow down the drop a small amount but the door is still dropping.

Stretching the spring by tapping on the bar it is to help keep the spring from rubbing against itself and making noise, including popping. . It doesn't "neutralize" the spring, whatever that means...

First is terminology. Spring shaft not rod or tube.
Drums and cables.
Bearing plates.

The drum needs to be up tight to the bearing plate on both sides. This will act as limiters to side to side movement. If you have play the spring shaft will move back and forth causing play. As you found out you always do the left first. All the bearing plates and center bracket need to be the same height above a level door.

Check to see how far away the drums are from the bearings and redo as needed.

 

[Hondaracer2oo4]

I have two LM8500 openers that I used to replace some Genie screw-drive openers when I put my lift in.

The rod the spring and pulleys are mounted to will always try to move left-right because of the spring issue mentioned. But if you have the bearing plates mounted properly and the pulleys mounted properly it should only be allowed to move like 1/8-1/4" total left to right and lateral movement is a non-issue.

I also had a bunch of movement out of the LM8500s when I first set them up. The rod used in my setup is soft, thus teh collar was crushing it a lot and causing it to be off-center and thus the excessive movement. I ended up redoing the collar setup on both (basically rotated them 90 degrees) and then worked to make sure the rod was centered, not too crushed and made sure the set screws were really torqued down properly.

I still get s little movement on the LM8500s and I know if I went to a stiffer rod (or even a solid one) I wouldn't get any, but for as little as they move now it isn't an issue. it is WAY better than when I first put them in, and I sure as hell can't justify replacing the rods (too much of a PITA). The doors I have are very heavy (part wood insulated Stanley Ones that were sitting in a warehouse for over 20 years) and I have no interest is messing with anything now that they are setup perfect.

So as far as the bearing plates and the pulleys mounted "properly" what are you referring to as "properly"? I will hang a plumb bob tomorrow right beside the jackshaft and mark it with a sharpy to see how much movement left to right it has. I will also pull a string in line with the jackshaft to check for up and down movement.

As far as the jackshaft I think mine too is soft, I noticed that after i repositioned the collar that the area where it had been clamped looked pinched, it took a whole lot of turning with the torque wrench to get 14 ftlbs, they just seemed to be turning for a long time at a certain torque( similar to when you know you are going to snap a bolt) What do you mean by rotated the collar? Mine I believe is the same on both sides, just the shaft on the lm is larger than the jackshaft in diameter. Do you have a one spring set up? If so that would give me hope to stay with the one as opposed to having to order three more springs and mounting plates.

 

[Hondaracer2oo4]

Liftmaster doesn't say anything about single-dual springs because it doesn't matter.

The second spring will not be able to support the weight of the door by it's self. It may slow down the drop a small amount but the door is still dropping.

Stretching the spring by tapping on the bar it is to help keep the spring from rubbing against itself and making noise, including popping. . It doesn't "neutralize" the spring, whatever that means...

First is terminology. Spring shaft not rod or tube.
Drums and cables.
Bearing plates.

The drum needs to be up tight to the bearing plate on both sides. This will act as limiters to side to side movement. If you have play the spring shaft will move back and forth causing play. As you found out you always do the left first. All the bearing plates and center bracket need to be the same height above a level door.

Check to see how far away the drums are from the bearings and redo as needed.

Do you think that the one of the drums just isn't against one of te bearing plates causing that lateral movement? I can't check until tomorrow morning. Should the bearing end plates have some type of additional support other than the factory set up which just mounts one screw at the top into the vertical wood framing and two bottom bolts into the angle iron supporting the horizontal track? Both of these attachment points are far away from the jackshaft bearing and give little stability to that point of the plate. If both of my drums are pushed out to the bearing plate already is there anything else I should look at?

 

[gnpenning]

Do you think that the one of the drums just isn't against one of te bearing plates causing that lateral movement?[/COLOR]R="DarkOI'm sure of it. [/OR]

I can't check until tomorrow morning. Should the bearing end plates have some type of additional support other than the factory set up which just mounts one screw at the top into the vertical wood framing and two bottom bolts into the angle iron supporting the horizontal track? Both of these attachment points are far away from the jackshaft bearing and give little stability to that point of the plate.As long as the connections are tight it's is enough.
Unless you have a really cheap product. Just because you paid good money doesn't mean you got good quality. In my world many of the name brand doors I would not put in my place. Big difference in quality of doors. Until you seen a good ones they all look the same.

If both of my drums are pushed out to the bearing plate already is there anything else I should look at?[/QUOTE. Not really. You could double check and make sure the spring shaft is the same distance from the header along it's length.
[/COLOR]

 

[Hondaracer2oo4]

Thanks everyone. The right side pulley was 3/4 " away from the bearing plate causing the walking. I slid that all the way out and now only get about 1/16" walk back and forth measured with a framing square placed on the header and the other leg sitting right over the shaft which I makrked. The 8500 still moves just a bit. Nothing concerning though. I got the other doors installed yesterday and the openers installed. They both have less movement. Thanks again everyone.