Crafstmans 139.53985D Garage Door opener doe snot close the door
I have installed the garage door opener listed in the subject but at first it would not open all the. It would stop about 10 inches short of fully open. I tried using the force adjustment screws but that did not help. It appears the distance of travel for the trolley is not long enough. I thought that maybe it would help to adjust where the chain starts on the sprocket so I took the whole thing down and moved the chair on the sprocket so that it would start at the point where I need the trolley to be for the door to be fully open. Now the door will not close all the way. It stops about 6 inches from closing. I guess I gained 4 inches. I am at a loss as to what to do. Can anyone help?