Chamberlain WD822KD 1/2 HP - Manual (Page 8)

FRONT RAIL
(TOP)
KEEP LARGER
HOLE ON TOP
8
Front Rail
(TO DOOR)
Window
Cut-Out
Screwdriver
Idler
Pulley
Hole
Tabs
Back Rails
(TO MOTOR UNIT)
Trolley
Tapered
End
Tapered
End
Inner Trolley
Wear Pads
Outer Trolley
Tapered
End
Tapered
End
To prevent INJURY from pinching, keep hands and
fingers away from the joints while assembling the rail.
WARNING
CAUTION WARNING
WARNING
The front rail has a cut out “window” at the door end
(see illustration). The hole above this window is
larger on the top of the rail than on the bottom. A
smaller hole 3-1/2" (8.9 cm) away is close to the rail
edge. Rotate the back rail so it has a similar hole
close to the opposite edge, about 4-3/4" (12 cm)
from the far end.
1. Remove the straight door arm and hanging
bracket packaged inside the front rail and set
aside for Installation Step 5 and 12. NOTE: To
prevent INJURY while unpacking the rail carefully
remove the straight door arm stored within the rail
section.
2. Align the rail sections on a flat surface as shown
and slide the tapered ends into the larger ones.
Tabs along the side will lock into place.
3. Place the motor unit on packing material to protect
the cover, and rest the back end of the rail on top.
For convenience, put a support under the front
end of the rail.
4. As a temporary stop, insert a screwdriver into the
hole 10" (25 cm) from the front end of the rail, as
shown.
5. Check to be sure there are 4 plastic wear pads
inside the inner trolley. If they became loose
during shipping, check all packing material. Snap
them back into position as shown.
6. Slide the trolley assembly along the rail from the
back end to the screwdriver.
ASSEMBLY STEP 1
Assemble the Rail & Install the
Trolley
To avoid installation difficulties, do not run the
garage door opener until instructed to do so.