sears craftsman 1/2hp garage door opener gear replacement help!
I removed the helical gear and sprocket from the opener, no problem....i ordered the part from sears...what came was a gear and sprocket that fit, but the top part where the chain sits in is a different circumference...is there any way to take the old gear off the old sprocket and put the new gear on the old sprocket? or do i need to extend the chain somehow? help! frustrated!