Connect Door Arm To Trolley - Chamberlain Power Drive PD420 Owner's Manual

INSTALLATION STEP 13

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" 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" 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.
• 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 28. Trolley will re-engage automatically when
opener is operated.
HARDWARE SHOWN ACTUAL SIZE
Nut 5/16"-18 Lock Washer 5/16"
Clevis Pin
Clevis Pin
5/16"x1-1/4" (Door Bracket)
5/16"x1" (Trolley)
Ring Fastener
Hex Screw
5/16"-18x7/8"
26
Inner
Trolley
Ring
Fastener
Straight
Door Arm
Door
Bracket
Curved Door Arm
Clevis Pin
5/16"x1-1/4"
Figure 1
Lock
Washers
5/16"
Nuts
5/16"-18
Door Bracket
Figure 2
Lock
Washers
5/16"
Nuts
5/16"-18
Cut this end
Figure 3
Outer
Trolley
Clevis Pin
5/16"x1"
Emergency
Release
Handle
Screws
5/16"-18x7/8"
Screws
5/16"-18x7/8"