Question about liftmaster Chamberlain Garage Door Opener Transmitter 300MC

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I have a Liftmaster 2000SD garage door opener and the other day the power at our house blinked on and off when the door was open. It wouldn't close after the power came back on so I manually closed the door. Later I went out and pushed to button to get the trolley to engage while the door was closed which worked but a few days later after the door opening and closing without problems it decided not to open. After looking everything over I realized the trolley was stuck in the middle of the track and I was able to get it reattached to the door and closed but now it won't open or close again. Not sure what to do

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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

  • 3197 Answers

SOURCE: Garage door will not open

Remove the cover and check the drive gear. It is white nylon and is just in front of the motor. It is most likely stripped.

Posted on May 18, 2009

  • 52 Answers

SOURCE: Liftmaster 1/2 HP Garage Door opener won't open or Close

The shaft on these garage door motors are not direct drive systems. You'll have to open up the box to see what the actual problem is. I have had stuff like this happen where a gear just slipped out of place.

Here is a link for a parts supplier. I don't know your model but it looks like most of the Liftmaster worm screw gears and drive gears are plastic so it's possible that one of them has cracked.

Posted on Feb 14, 2010

  • 23 Answers

SOURCE: We have a Liftmaster Professional Formula One

did you check the spring tention or it could be a problem with the track

Posted on Sep 13, 2010

  • 504 Answers

SOURCE: Liftmaster Formula One. Garage

Sounds like the gears are stripped.

Open the housing and see if there are white plastic shavings inside.

If so

You can get a gear kit and fix it yourself $ 35 - $50

Or for around $ 125.00 get a pro to fix the problem and lube, adjust, service the door and opener.

You pretty much have to take the unit apart all the way - it's not a simple project but it is doable for a diyer with reasonable skills 1-2 hours.

Follow the instructions step by step and don't cheat by leaving the gear thats hard to get to. The wear pattern on it will chew up your new gear in a few months and you will be doing it all over again.

Hope this helps

Posted on Mar 30, 2011

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