Chamberlain 248730 - Manual (Page 19)

18
Installation
STEP 9 Connect the door arm to the trolley
Installation will vary according to the garage door type. Follow the instructions which apply to your door.
OPTION A
SECTIONAL DOORS
IMPORTANT: The groove on the straight door arm MUST face away from the curved door arm.
1. Close the door. Disconnect the trolley by pulling the emergency release handle.
2. Attach the straight door arm to the outer trolley using the clevis pin. Secure with the ring
fastener.
3. Attach the curved door arm to the door bracket using the clevis pin. Secure with the ring
fastener.
4. Bring arm sections together. Find two pairs of holes that line up and join sections. Select holes
as far apart as possible to increase door arm rigidity and attach using the bolts, nuts, and lock
washers.
5. Pull the emergency release handle toward the garage door opener until the trolley release
arm is horizontal. The trolley will re-engage automatically when the garage door opener is
activated.
NOTE: If the holes in the curved door arm and the straight door arm do not align, reverse the straight
door arm, select two holes (as far apart as possible) and attach using bolts , nuts, and lock washers . If the
straight door arm is hanging down too far, you may cut 6 inches (15 cm) from the solid end.
HARDWARE
Hex Bolt 5/16"-18x7/8"
Nut 5/16"-18
Lock Washer
5/16" -18
Clevis Pin 5/16"x1" Clevis Pin 5/16"x1-1/4"
Ring Fastener
Straight
Door Arm
Curved
Door
Arm
(Groove
facing
out)
CORRECT
Straight
Door
Arm
Curved
Door
Arm
INCORRECT
Lock Washer
5/16" -18
Nut
5/16"-18
Hex Bolt 5/16"-18x7/8"
Clevis Pin 5/16"x1-1/4"
Ring Fastener Clevis Pin
5/16"x1"