# Garage door opener closes for 5 inches and then automatically tries to open 5 inches



## omnipotent32 (Jul 6, 2009)

Hi,

I have a Craftsman ½ HP Garage door opener that I just completed replacing a drive gear for. After putting the entire thing back together with a new drive gear as per instructions, the garage door is no longer working properly. It first tries to close the garage door for about 5 inches and the reverses and opens it 5 inches. I have checked the obstruction sensors and they do not indicate that the garage door opener thinks that it has been obstructed.

I have noticed this happening even when I disengage the chain from the drive gear entirely and I notice that the drive gear first spins to close the garage door and then automatically reverses its spin and tries to open the garage door even when the chain is not connected to it.

I have tried playing around with the up and down settings as well as the downward and upward force adjustments. So far the garage door appears to be unresponsive to these tweaks save for a quicker reversal of the garage door after it hits the floor when I reduced the downward force.

Help!


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## JohnWill (Oct 19, 2002)

Well, that sounds like what I see when I screw up the adjustments for how much force the drive has. Mine has a switch with a spring that senses when there's too much downward drive pressure and reverses the door. If yours has the same thing, check to see if that's working properly.


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## kenny111111 (Dec 11, 2008)

is there 2 screws on the side to increase & decrease the "travel limit". i just replaced a gear on mine thats where mine needed adjusted.

good luck.


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## omnipotent32 (Jul 6, 2009)

I don't believe its an up/down limit issue since the opener is doing the exact same thing even when the chain is not mounted onto the drive assembly.

What does a switch with a spring that senses downward pressure look like?


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## Drabdr (Nov 26, 2007)

omnipotent32 said:


> I don't believe its an up/down limit issue since the opener is doing the exact same thing even when the chain is not mounted onto the drive assembly.
> 
> What does a switch with a spring that senses downward pressure look like?


Actually, that is a good question.:up: If it's possible, can you take a picture of your base unit/track and post here?

Typically, there are two little switches (typically little plastic arms sticking down that the main arm connected to the garage door would hit) with two wires attached, leading back into the main opener.

I agree with Kenny and John. I would start with the force screws, and I would also look at the limit switches. NOTE: The limit switches are on the horizontal track; not the obstruction sensors on the door. If you still have the instruction manual for the opener, it should have the force adjustment procedure. It wouldn't hurt to try.


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## JohnWill (Oct 19, 2002)

Well, my force sensing switches have a spring and an over-center lever that senses when pressure is on the drive in either direction and toggles the direction of the motor. Actually, I think when it's going up, it just stops if I recall correctly.


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## wacor (Feb 22, 2005)

maybe the obstruction sensors are faulty?

unfortunately I do not believe there is a way to bypass them.

I had issues with the sensors sometimes being out of adjustment just enough that at times the vibration of the door would tell them to stop the door. 

I would take them off the mounts temporarily and tape them together so you know for certain they are not at fault from shaking or moving. Not likely the problem as you have tried the closer with it unhooked from the track. but ya never know


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## omnipotent32 (Jul 6, 2009)

Hi Everyone,

Still have a problem but I have eliminated some potential fixes. 

1. It has nothing to do with the upward and downward limit switches as I have adjusted them so that they are far away from the main arm and when it travels it doesn't come close to touch either of the limits. It just advances and reverses the same distance each time.

2. I have confirmed that it is not an obstruction because I intentionally obstructed the garage door and it reversed earlier and rose a bit higher than before (which is a product of it no longer travelling down as much as it did before due to the obstruction but it rose the same amount so the net affect was a higher stopping position).

2. B, Also, when obstructed, the light flashes for 5 seconds. This doesn't happen when I get the problem.

3. It has nothing to do with the force switches as I have adjusted both all the way up and all the way down with no change in performance.

Could it be that my circuit board is screwed up?


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## wacor (Feb 22, 2005)

I would still move the obstruction sensors together. When mine acted up the lights did not blink. The laser just did not hit the other sensor and it thus would not allow it to go up.


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## JohnWill (Oct 19, 2002)

Clearly, it could be an electronic issue, or perhaps the motor or drive components simply having too much drag and causing it to think it has to reverse. It sure sounds like a mechanical issue, but it's impossible to tell from this end of the connection.


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## omnipotent32 (Jul 6, 2009)

Would posting videos of the problem help?


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## JohnWill (Oct 19, 2002)

I think this is an "observe and diagnose" issue, but it's pretty hard to "try" things and see the reaction from a video.  It might help someone here come up with an idea, hard to say.


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