Assembly Section - Pages 8 - 11 Fasten T-Rail To Opener; Attach Chain To Sprocket, Install Sprocket Cover - Chamberlain Series 1200 Owner's Manual

Assembly Step 1
Attach the T-rail to the Opener
For Models 1255R, 1245R, and 1240R
See page 9 for Models 1256R and 1246R.
• Remove the two washered screws mounted in top
of opener
• Align T-rail at an angle with opener so one hole in
T-rail and opener line up.
• Thread one of the washered screws part way in.
Use only these screws! Use of any other screws
will cause serious damage to door opener.
• Align T-rail and styrofoam over opener sprocket.
Cut tape from T-rail, chain and styrofoam.
• REMOVE STYROFOAM.
Step 2 Attach Chain to Sprocket - Liftmaster 1140, 1145 & 1155 Disk
Assembly Step 2
Attach Chain to Sprocket and
Install Sprocket Cover
For Models 1255R, 1245R, and 1240R
• Position chain over the opener sprocket. If
necessary, loosen the outer nut on the trolley to
obtain more chain slack.
• Insert the second washered screw.
CAUTION: Use only the screw previously
removed from opener!
• Tighten both screws securely through the T-rail
into the opener as shown.
Install the sprocket cover:
• Insert the back tab in the opener slot. Squeeze the
cover slightly and insert the front tab in the slot on
the mounting plate.
Sprocket
Sprocket
Cover
Cover
Tab Slot
Front Tab Slot
Mounting
Back Tab Slot
Top of Opener
Mounting
Plate
Plate
Proceed to Assembly Step 3, page 11.
Step 1 Attach Tee Rail To Opener Chassis - Liftmaster C
To fasten rail, use only those screws mounted
in top of the opener. Any other screws will
cause serious damage to the opener.
USE ONLY THIS
TYPE AND SIZE
SCREW
10/8/91
Serious injury can result if fingers become
entangled in moving opener sprocket. Attach
sprocket cover securely. Never operate opener
while your hand is near the opener sprocket.
USE ONLY THIS
TYPE AND SIZE
SCREW
8
CAUTION
10/4/91
Washered Screw
5/16"-18x1/2"
T-rail
Hole
Chain
WARNING
CAUTION
Washered Screw
5/16"-18x1/2"
Sprocket
Styrofoam
Opener