Garage door top big long steal beam will bulge, after tenant tri

Garage door opener chain falls off the wheels. After tenant tried to repair himself, now the the whole steel beam will bulge when press start. 

He seems put the chain back on wheels, but when press start, the big round long steel beam will now bulge.

it is now disconnect. 

Someone knows what goes wrong and how to fix? 

所有跟帖： 

• how can a steal beam bulge? picture ? -win963852741- ♂ (0 bytes) () 08/28/2016 postreply 15:26:06

• 我查了99% certain problem is the chain goes to opposite direction. -君临萌萌哒- ♂ (90 bytes) () 08/28/2016 postreply 15:51:28