Chamberlain 1280 - 1/2 HP - Manual (Page 11)

Header
Bracket
Belt Pulley
Bracket
Temporary
Support
Header Wall
Garage
Door
The Chamberlain Group, Inc.
Liftmaster Synchro Drive
Attach Tee Rail to Header Brack
5/16/92
T-rail
Clevis Pin
5/16"x2-3/4 "
Ring Fastener
Header Bracket
Belt Pulley
Bracket
T-rail
INCREASE DOWN TRAVEL
INCREASE
UP TRAVEL
• Position the opener on the garage floor below the
header bracket. Use packing material as a
protective base.
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 T-rail to clear the
spring.
• Position the belt pulley bracket against the header
bracket.
• Align the bracket holes and join with a clevis pin as
shown.
• Insert a ring fastener to secure.
11
Installation Step 3
Attach the T-rail to the Header Bracket
Clevis Pin
5/16" x 2-3/4" Ring Fastener
Hardware Shown Actual Size