Mueller Roll-Up Door C250 - Manual (Page 12)

12 877-2-MUELLER
STEP 14: MAKE SURE THE TOP OF GUIDE IS BENT
STEP 15: CHECK DOOR OPERATION
A Lower and raise the door to test door operation.
A Bend the flap at the top of the guide
over the headstop with a Vise-Grip or
an adjustable wrench.