# Garage door does not open fully...sometimes



## SilverSword (Jan 20, 2010)

Hi all,

I have a Liftmaster SDR2000, 1/2 HP Garage door system that was installed 10 years ago. During the recent cold spell, the Garage door would not open fully. However, on occasions, it would go all the way. Some more information:

* It's a screw drive garage door opener

* I'm able to disengage the motor and open the door manually with minimal effort

* When it does not open fully, it always stops at the same point, as if there is something stopping the screw drive mechanism. I used a step ladder to see if there is something on the center drive or the two sides but I cannot see anything that would block the mechanism

* I adjusted the upward force to maximum but that has not helped so far

No one would confuse me for Macgyver, but these days I need to save $$ when possible. 

Any tips on where the problem might lie would be appreciated!:beer:


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## 911handyman (Jan 20, 2010)

Have you tried to lubricate to screw drive try some wd-40 or lithum grease. Cold weather causes the springs to become stiff. As grease does the same. If that does not work check amps with a multimeter. Should be at least 9-12amps. hope this helps.


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## SilverSword (Jan 20, 2010)

911handyman said:


> Have you tried to lubricate to screw drive try some wd-40 or lithum grease. Cold weather causes the springs to become stiff. As grease does the same. If that does not work check amps with a multimeter. Should be at least 9-12amps. hope this helps.



Ok, I'll try a lithium lube first. 

I'm not that handy, so can you please explain how and where to check the amps with a multimeter? I think I have a multimeter but where exactly am I measuring the current? Thanks


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## TxBuilder (Jan 20, 2010)

Is that all it's doing? Is it making and noises? A banging or whining?


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## SilverSword (Jan 20, 2010)

TxBuilder said:


> Is that all it's doing? Is it making and noises? A banging or whining?



I did not hear any "whining" type sounds but I do hear a heavy "rolling" type noise as the opening mechanism passes over some points along the screw. It almost sounds as if it is trying to ride over an obstacle.


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## 911handyman (Jan 20, 2010)

Look for this to see if damaged or if you can adjust this is most likely your problem. It is called a limit switch visit the link. 41D3452 Lift-Master Limit Switch Assembly


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