If you pull the emergency release lever while the door is open you can cause the garage door to shut rapidly.
Manually close liftmaster garage door.
Once the lever is disengaged you should be able to open and close your garage door by hand.
In this post you will find downloadable links to all models of liftmaster garage door opener manual.
This will cause the trolley to move into position and reconnect to the garage door.
8160w 8160wb 8165w 8164w 8155w.
It should move smoothly and only require a little force to open and close.
A word of warning.
Liftmaster garage door opener models 8160w 8160wb 8165w 8164w and 8155w.
Try opening the garage door with the remote and see what happens.
Before you set your garage door opener with your garage door it s crucial to read the owner s manual.
These steps should fix most doors.