Chamberlain Opener Motor Acting Screwy
I searched all the previous posts in this forum and Home Repair (189 posts) and couldn't find anything even close to the problem I'm having...
I had a Chamberlain Liftmaster 1/2hp opener (Model 2280) and sectional garage door installed almost 2 years ago. Occasionally the sensors got misaligned, but everything worked great until the other day. My wife pressed the button inside our house and the door opened, got about halfway up and stopped. She pressed the button again and the door went down about a foot, then went up about a foot and stopped. She tried this a couple more times with same results and then called me.
I crawled under and disengaged the door from the track. Checked the sensors, they're perfectly aligned and no blinking overhead lights. Tried the button again with the door disengaged from the track and the motor ran forward for two seconds, then reversed for two seconds and stopped. I then took the belt off. I watched the motor spin for two seconds one direction, then reverse itself for two seconds and shut off.
I've tried turning the up travel screw with no luck, same for down travel screw. (They're now back in the same position as when the problem first occurred.) I took the motor housing cover off and no gears appear to be broken, no wires are loose. I've even tried resetting the learn button (hey I'm desperate), but no luck. I also tried changing the down and up force with no change.
The problem occurs with the remotes as well as the switches inside the garage and inside the house. No one messed with the opener or tried to adjust any of the screws before the problem first occurred. The garage door moves freely whether you're pushing it up or pushing it down from the inside.
Any help would be appreciated. Thank you in advance.