Connect Door Arm To Trolley (Sectional Door); Clevis Pin 5/16"X2-3/4; Clevis Pin 5/16"X1-1/4; Clevis Pin 5/16"X1 - Chamberlain 1280 Owner's Manual

Installation Step 12
Connect Door Arm to Trolley
Follow instructions which apply to your door
type as illustrated below and on page 23.
Make sure garage door is fully closed. Pull the emergency release handle to disconnect the outer trolley
from the inner trolley. Slide the outer trolley back (away from the door) about 2" as shown in Figures 1-3.
Figure 1:
• Fasten straight door arm section to outer trolley
with the 5/16"x1" clevis pin. Secure the connection
with a ring fastener.
• Fasten curved section to the door bracket in the
same way, using the 5/16"x1-1/4" clevis pin.
Outer Trolley
Ring
Fastener
Door
Bracket
Clevis Pin
5/16"x1-1/4"
Figure 3:
• If holes in curved arm are above holes in straight
arm, disconnect straight arm. Cut about 6" from
the solid end. Reconnect to trolley with cut end
down as shown.
• Bring arm sections together.
• Find two pairs of holes that line up and join with
screws, lock washers and nuts.
Hardware Shown Actual Size
Nut 5/16"-18 Lock Washer 5/16"
Clevis Pin
5/16"x1-1/4" (Door Bracket)
5/16"x1" (Trolley)
Proceed to Adjustment Step 1, page 24. Trolley will re-engage automatically when the opener is operated.
SECTIONAL Doors Only
Inner Trolley
Clevis Pin
5/16"x1"
Straight
Door Arm
Curved
Door Arm
Figure 1
Hole Alignment Alternative
Ring Fastener
Clevis Pin
Hex Screw
5/16"-18x7/8"
Figure 2:
• 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.
Washers
Nuts
5/16"-18
Door Bracket
Nuts
5/16"-18
22
Lock

Rope

5/16"
Manual
Release

Handle

Screws
5/16"-18x7/8"
Figure 2
Lock
Washers
5/16"
Screws
5/16"-18x7/8"
Cut This End
Figure 3