Question about Sears Craftsman LiftMaster Chamberlain Garage Door Opener Wireless Keypad Model 976LM Security+

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Sears Craftsman 3/4

Can you help?

My gears were finally shredded on my 15+ y/o Crafstman 1/2hp motor - so I replaced it with a 3/4 new model. I left the door hardware and simply replaced the motor, kept the chain. I have a 15 ft wooden door.

It worked very well for about two days after I had dialed it in using the force/travel adjustments, but yesterday, it started bouncing up off the floor. I turned down the down travel as far as I could go (and it still bounced). It looks like its really pushing hard when the door is closed, then reverses.

I played with both force and travel - and nothing seems to work.

The upward travel works like a charm, I can dial that in to stop 2-3" from the stop bolt - and it works as it shoud. Down travel seems "broken."

Any thoughts?

Posted by on

  • tvaughn243 Jan 09, 2009

    It was a new motor - so I assumed that it was right when it came to me in the box. I opened up the case, and sure enough had a broken part.



    The small metal "t" that travels between the up and down travel limits was broken. Travel assembly was replaced - and door works PERFECTLY.

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Open up the caseand look at the travel assy. Sometimes the limit (up or down) do fall off the assy. Just snap it back on.

Posted on Jan 09, 2009

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