Chamberlain LiftMaster PROFESSIONAL SECURITY+ 2500DC Manuel D'instructions page 11

Header Wall
Header Bracket
Belt Pulley Bracket
Torsion
Spring
Rail
Garage
Door
Foam Packaging
INSTALLATION STEP 3
Attach the Rail to the Header
Bracket
• Position the opener on the garage floor 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.
Clevis Pin
5/16"x2-3/4"
HARDWARE SHOWN ACTUAL SIZE
Clevis Pin
5/16"x2-3/4"
11
Ring Fastener
Header Bracket
Belt Pulley
Bracket
Rail
Opener Carton or
Temporary
Support
Ring Fastener