Replies

1. 
   Stilletto | Sep 02, 2006 03:23pm | #1

   Pull the cord that hooks the door to the opener shaft.  Operate the door by hand and see if it works fine. 

   I am not familar with liftmaster openers,  what kind of stuff is attached to it?  Sensor eyes on the tracks?  Door stops on the shaft?  A little info might go a long way on this one. 

       

    

2. 
   MojoMan | Sep 02, 2006 03:27pm | #2

   Have you had an electrical storm recently? Lightening can blow electronic controls in GDO's. It could be a blown speed sensor inside the motor/contol unit on the ceiling.

   Al Mollitor, Sharon MA

   http://moosehilljournal.blogspot.com/

3. 
   edwardh1 | Sep 02, 2006 03:57pm | #3

   limit switch ?
   force adjustment on motor?

4. 
   DanH | Sep 02, 2006 03:58pm | #4

   Yeah, first make sure the door moves freely by hand (after releasing it from the trolley). Then check that electric eyes are properly lined up and not being blocked by trash, etc. Then try operating the opener with the door disconnected.

   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
5. 
   BillHartmann | Sep 02, 2006 04:20pm | #5

   There are TWO different sets of adjustment. One is for travel (limit).

   The other is force limit. It will stop if the force is too high. And if it is misadjusted minor balance or friction can stop it.

   First disconnect the door from the GDO.

   The manuall move it through the full range. And the door should be balance such as at mid open it stays there. At 1/4 open it should close when released and at 3/4 open it should open all of the wall.

   Then try the GDO WITHOUT the door connected. If it travels the normal amount then the problem is with the lift force adjustment.

   It is possible that the travel limit switch is broken.

   I don't think that the sensors affect open.

   But check the adjustment. And I had a problem with the manual pull rope dropping in front of one on closing that would cause it to stop. And I know of some that had a problem with direct sunlight hitting the receiver.

   Also does the light flash? Some units use that a fault signal.

   BTW, Liftmaster is a well know brand that is only sold through dealers and comes with full piece rails and I believe heaveir parts.

   It is made by Chamberlain and is similar in design. Chamberlain also makes similar units for Sears.

1. 
   Ledebuhr1 | Sep 02, 2006 05:41pm | #6

   Thanks for your help,

   I can't move the GD through its full range of motion because the trolly is nearly at the front of the rail. For me to manualy move the door up, the trolly would need to be all the way back next to the GDO.

   The lights do not blink. It just stops when the door is 2" off the floor.

1. 
   BossHog | Sep 02, 2006 06:06pm | #7

   "I can't move the GD through its full range of motion because the trolly is nearly at the front of the rail."

   Are you sure about that? Try pulling the handle and see if you can move it up.

   I've haven't seen a GDO yet that wouldn't let the door go all the way up or down regardless of the position of the catch thingy.
   Q: What do you call a couple that uses the rhythm method of birth control?
   A: Parents.

2. 
   Heck | Sep 02, 2006 06:24pm | #8

   You should be able to manually disconnect the GD from the trolley, usually by pulling on a cord connected to the trolley bracket.

   You may have to pull toward the door or away to disconnect.

   If this doesn't work, manually disconnect the attachment bracket from the door or trolley (whichever is easier) and then check the operation of both the opener and the door.be heck of a tagline...

3. 
   rjw | Sep 02, 2006 08:12pm | #9

   As mentioned, the door needs to be able to be disconnected from the trolly should a power outage occur. Usually (not always) there is a "L" shaped lever (might have a string attached for easier access.)I have seen a few cases in doors where the trolly has somehow gotten past the lower limit switch, and then when opening, it trips the switch right after starting up and stops moving.In the cases I've seen, the limit switch is just a small length of metal hanging down down which is pushed by a part of the trolley.I forget how I've readjusted them, but finding if that is the the problem is the most important step.BTW: that opener should have a electric eye reverser (they have been required of the manufacturers since 1992) although sometimes people eliminate them (or mount them out of the way directly adjacent so they don't accomplish anything.)BUT, the electric eye only reverses direction when the door is descending - it should not affect it while rising.

   Fighting Ignorance since 1967

   It's taking way longer than we thought

1. 
   BillHartmann | Sep 02, 2006 09:05pm | #12

   AFAIK the Chamberlain/Liftmaster/Craftmans (also Access Master, Garage Master, Master Mechanic, Formula 1, Security+, Link, Billion Code, True Value, True Guard, Raynor) have never used anything on the chain or belt to set the travel limit.They all do it off the motor drive chain someplace.Which means that the it can get off indexed. Which I have had open on my older chain drive (1979). But I don't see it happen that it can be off that far. But I have not looked in detail at the inners of the new ones to see exactly how they are connected.BTW, here is a great resource for information on GDO.http://www.aaaremotes.com/liftmaster.htmlLink on the right for all kinds of brands.They also have schematics for many Chamberlain, Liftmaster, and Genie models.http://www.aaaremotes.com/gadooprepaan.htmlAnd manufactures instruction manuals, programming information and replacement remotes.Looks like it would be a good resouce for your clients.

1. 
   junkhound | Sep 03, 2006 12:21am | #13

   Here is another similar very simple garage door anomaly, probably my fault for not adding a clamp at installation; but, Moral is to look at the very basics FIRST.

   Brother, BIL,  and I installed door for Mom in IL 2-1/2 years ago the week after Pop died, -14 F in January.  Had not had a car inthat garage for 50 years due to tool and bicycle collections.  Mom reported last month the door would not open, brother went over and reported it worked fine manually, only spent 5 minutes looking at it, figured she wouldn't need it till bad weather anyway and I could fix it next time in town (2000 miles away).

   So BIL visits before I do, and finds the problem. Now, BIL is not the DIY Brother and I are (both built own houses, etc.) although he teaches High School physics.

   I'd installed the electrical outlet facing down to keep out dirt and condensation (unheated), using an old outlet left in Pops supplies.  Turns out the vibration of 2-1/2 years of operation shook the plug loose with the ground lug still holding it in. BIL shoved it all the way back in and everything worked fine.

   Own house has spec grade outlets facing down and none have shook out over 35 years -- always a new failure mode to learn.

2. 
   rjw | Sep 03, 2006 04:15am | #14

   I don't know brands, but there are openers out there with a "hanging" switch on the track activated when the trolly pushes the lever.If I created the impression the switch itself was on the chain/belt, then I misspoke.

   Fighting Ignorance since 1967

   It's taking way longer than we thought

3. 
   BillHartmann | Sep 03, 2006 07:02am | #15

   I have not seen one with where the trolley activates the stop/reverse.But I have seen several that use "cams" or fingers on the chain. One the finger hit ordinary toggle switch.But they wheren't Chamberlain/Liftmaster/Craftsman. Those all use travel switchs that are internal to the drive head.

4. 
   DanH | Sep 03, 2006 03:31pm | #16

   My MIL had an old Chamberlain screw drive unit that I'm pretty sure had some sort of external limit adjustment, though I can't remember the details.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

5. 
   BillHartmann | Sep 03, 2006 07:29pm | #23

   You might be right on the screw drives. I have never seen a Chamberlain version. But I have seen other brands with them.BTW, it seems that Chamberlain/Liftmaster's market was chain drive. While Genie's was screw drive. Both make the other models, I guess just to say that they have them. But at least around here it is either Chamberlain/Liftmaster chain or Genie screw drive.Now both of them have belt drive versions.

6. 
   rjw | Sep 03, 2006 09:28pm | #25

   That's what I am talking about. the toggle switch version.I think at least some of the one's with the travel stops in ther head still use some sort of device on the chain toi activate, although I haven't made a study of this.I_think_ the "toggle switch" types are the screw driven ones.

   Fighting Ignorance since 1967

   It's taking way longer than we thought

4. 
   DanH | Sep 02, 2006 08:17pm | #10

   Hold the release while you lift up on the door. The release should allow the door to go either way past the trolley.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

1. 
   Ledebuhr1 | Sep 02, 2006 08:43pm | #11

   Thanks for all your help.

   I went out and looked at it and found the problem. It has a broken spring. I got the door up, but boy was it heavy.

   Ill have the service tech from the garage door company come out and put a new one on. I know putting on a spring can be dangerous.

1. 
   Danno | Sep 03, 2006 03:53pm | #17

   You may want to ask the installer to put on a "spring keeper" (usually just a cable running through the center of the spring) if it doesn't already have one--I had a spring break (not the kind the college kids take) and it smashed the bracket at the end (may have done so even with a keeper, but at least it doesn't end by falling on your car or shooting across the garage!).

2. 
   Stilletto | Sep 03, 2006 04:53pm | #18

   THe spring keepers are used on the springs that run from parrallel with the tracks,  are a great idea.  I started using them a while back,  when on a repair I found the other half of a spring in the drwall. 

        

    

3. 
   DanH | Sep 03, 2006 04:58pm | #19

   Yeah, I put them on our door, and on the couple of doors I fixed for other folks. If you're working around the door it's good for your own safety, and I've found they help when one has to hook up the springs.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

4. 
   Stilletto | Sep 03, 2006 05:04pm | #20

   They don't help on overhead torsion springs cause the shaft runs through the springs. 

   I can't remember the last time I installed a door with the tension springs just alot of repairs.      

    

5. 
   DanH | Sep 03, 2006 05:37pm | #22

   True, I think torsion springs are much more common of late, but there are still lots of doors out there from 20-30 years ago when tension springs were the norm, at least in this part of the country.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

6. 
   BillHartmann | Sep 03, 2006 07:31pm | #24

   I wonder if that has to do with the size and weight of the door.All of the 16 and 18 ft doors that I have seen are torsion spring.Only see the side spring on smaller doors.

7. 
   DanH | Sep 03, 2006 10:02pm | #26

   We've got a 16 foot hardboard door (a lot heavier than your standard steel, and heavier than many wood doors). It has extension springs.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

6. 
   PhillGiles | Sep 03, 2006 05:19pm | #21

   Ton of good advice here already, but let me ask some real basic with electronics:

   1. Is there a reset button ?  Could be big, could be small, could even be obscure, but most electronic devices have some sort of reset routine.
   2. Have you checked the "Doesn't work" section of the GDO's manual (look for a manual on the net if you don't have one in hand) ?
   3. As with all electronic devices, sometimes the first level of repair is to disconnect it from the power source for a while.  This will generally force a reset; and, will let components cool down (you checked for hot-spots, right ?).

    

   Phill Giles

   The Unionville Woodwright