Chamberlain 3280 1/2 HP Garage Door Opener User Manual


 
21
INSTALLATION STEP 12
Connect Door Arm to Trolley
Follow instructions which apply to your door type as
illustrated below and on the following page.
SECTIONAL DOORS ONLY
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" (5 cm) as
shown in Figures 1, 2 and 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.
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.
Figure 3, Hole alignment alternative:
If holes in curved arm are above holes in straight
arm, disconnect straight arm. Cut about 6"
(15 cm) 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
bolts, lock washers and nuts.
Pull the emergency release handle toward the
opener at a 45° angle so that the trolley release
arm is horizontal. Proceed to Adjustment Step 1,
page 23. Trolley will re-engage automatically when
opener is operated.
Ring
Fastener
Door
Bracket
Clevis Pin
5/16"x1-1/4"
Curved
Door Arm
Straight
Door Arm
Clevis Pin
5/16"x1"
Inner Trolley
Outer Trolley
Lock
Washers
5/16"
Nuts
5/16"-18
Door Bracket
Bolts
5/16"-18x7/8"
Emergency
Release
Handle
Lock
Washers
5/16"
Nuts
5/16"-18
Bolts
5/16"-18x7/8"
Cut This End
Figure 1
Figure 2
Figure 3
Lock Washer 5/16"
Nut 5/16"-18
Ring Fastener
Hex Bolt
5/16"-18x7/8"
Clevis Pin
5/16"x1" (Trolley)
Clevis Pin
5/16"x1-1/4" (Door Bracket)
HARDWARE SHOWN ACTUAL SIZE