Attach The Rail To The Header Bracket; Position The Opener - Chamberlain Liftmaster Security+ 3280M-267 1/2HP Owner's Manual

INSTALLATION STEP 3

Attach the Rail to the Header Bracket

• Position the opener on the garage fl oor below the header
bracket. Use packing material as a protective base.
NOTE: If the door spring is in the way you'll need help.
Have someone hold the opener securely on a temporary
support to allow the rail to clear the spring.
• Position the rail bracket against the header bracket.
• Align the bracket holes and join with a clevis pin as shown.
• Insert a ring fastener to secure.
HARDWARE SHOWN ACTUAL SIZE
Clevis Pin 5/16"x2-3/4"
INSTALLATION STEP 4

Position the Opener

Follow instructions which apply to your door type as
illustrated.
SECTIONAL DOOR OR ONE-PIECE DOOR WITH
TRACK
A 2x4 laid fl at is convenient for setting an ideal
door-to-rail distance.
• Remove foam packaging.
• Raise the opener onto a stepladder. You will need help
at this point if the ladder is not tall enough.
• Open the door all the way and place a 2x4 laid fl at on
the top section beneath the rail.
• If the top section or panel hits the trolley when you
raise the door, pull down on the trolley release arm to
disconnect inner and outer sections. Slide the outer
trolley toward the motor unit. The trolley can remain
disconnected until Installation Step 12 is completed.
Trolley
Release Arm
ENGAGED
ONE-PIECE DOOR WITHOUT TRACK
A 2x4 on its side is convenient for setting an ideal
door-to-rail distance.
• Remove foam packaging.
• Raise the opener onto a stepladder. You will need help
at this point if the ladder is not tall enough.
• Open the door all the way and place a 2x4 on its side
on the top section of the door beneath the rail.
• The top of the door should be level with the top of the
motor unit. Do not position the opener more than 4"
(10 cm) above this point.
Ring Fastener
RELEASED
10
Header Wall
Header Bracket
Belt Pulley
Bracket
Garage
Door
Temporary
Support
To prevent damage to garage door, rest garage door
opener rail on 2x4 placed on top section of door.
Rail
2x4 is used to determine
Door
the correct mounting
height from ceiling.
Header
Bracket
Top of Door
2x4 is used to determine
the correct mounting
height from ceiling.
Ring
Header
Fastener
Bracket
Clevis Pin
5/16"x2-3/4"
Belt Pulley
Bracket
Rail