Hang The Opener - Chamberlain LiftMaster 3275C Owner's Manual

INSTALLATION STEP 5

Hang the Opener

Three representative installations are shown. Yours may be
different. Hanging brackets should be angled (Figure 1) to provide
rigid support. On finished ceilings (Figure 2 and Figure 3), attach
a sturdy metal bracket to structural supports before installing the
opener. This bracket and fastening hardware are not provided.
1. Measure the distance from each side of the motor unit to the
structural support.
2. Cut both pieces of the hanging bracket to required lengths.
3. Drill 3/16" pilot holes in the structural supports.
4. Attach one end of each bracket to a support with
5/16"-18x1-7/8" lag screws.
5. Fasten the opener to the hanging brackets with
5/16"-18x7/8" hex bolts, lock washers and nuts.
6. Check to make sure the rail is centered over the door (or in line
with the header bracket if the bracket is not centered above the
door).
7. Remove the 2x4. Operate the door manually. If the door hits
the rail, raise the header bracket.
8. Grease the top and underside of the rail surface where the
trolley slides with rail grease.
NOTE: DO NOT connect power to opener at this time.
HARDWARE SHOWN ACTUAL SIZE
Lag Screw 5/16"-18x1-7/8"
Hex Bolt
5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18
To avoid possible SERIOUS INJURY from a falling garage door
opener, fasten it SECURELY to structural supports of the
garage. Concrete anchors MUST be used if installing ANY
brackets into masonry.
Figure 1
Measure
Distance
Bolt 5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18
Figure 2
Hidden
Support
Bracket
(Not Provided)
Bolt 5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18
Figure 3
Lag Screws
5/16"-18x1-7/8"
Bolt 5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18
12
Structural
Supports
Lag Screws
5/16"-18x1-7/8"
FINISHED CEILING
Lag Screws
5/16"-18x1-7/8"
(Not Provided)
Bolt 5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18
FINISHED CEILING
(Not Provided)
Bolt 5/16"-18x7/8"
Lock Washer 5/16"
Nut 5/16"-18