Tag: idler bolt

Liftmaster Garage Door Opener: Idler Bolt sheared off

Impressed, I am not, when my garage door opener stopped working. I have a Chamberlain LiftMaster garage door opener, model 1355C 1/2 hp in chain drive. The failure of the idler bolt was catastrophic.

There is a metal gear on the motor, which moves a metal chain in an oval, opening and closing the garage door. At the door side, opposite to the door opener, the chain makes a 180 degree turn back to the opener on a plastic wheel, called the idler. The wheel is fine, but the metal bolt that keeps the idler attached to the metal rail sheared off at the threads.