Craftsman 139.53964SRT Owner's Manual page 9

ASSEMBLY STEP 2
Fasten the Rail to the Motor Unit
• Insert a 1/4"-20 x 1-3/4 bolt into the cover
protection bolt hole on the back end of the rail as
shown. Tighten securely with a 1/4"-20 lock nut.
• Remove the two bolts from the top of the motor
unit.
• Attach spreaders to the U bracket by snapping
them into place.
• Place the U bracket, flat side down, on the motor
unit and align the bracket holes with the bolt holes.
Fasten with the previously removed bolts.
• Align the rail assembly with the top of the motor
unit. Slide the rail end onto the U-bracket, all the
way to the stops that protrude on the top and sides
of the bracket.
HARDWARE SHOWN ACTUAL SIZE _"r'-'_'_"l
q Lock Nut
Bolt 1/4"-20 x I-3/4 1/4"-20
To avoid SERIOUSdamage to garage door opener, use
ONLYthose bolts/fasteners mounted in the top of the
opener.
Motor Unit
Bolts _ Sprocket
"U" Bracket
Bolt
Cover
Logk Nut
SLIDE RAIL TO STOPS
ON TOP AND SIDES
OF BRACKET
ook Belt Spreader
into Back Slots,
then Snap Tab
Into Front SIot
ASSEMBLY STEP 3
Install the Idler Pulley
• Lay the belt beside the rail, as shown. Grasp the
end with the hooked trolley connector and pass
approximately 12" (30 cm) of belt through the
window. Keep the ribbed side toward the rail, and
allow it to hang until Assembly Step 5.
• Remove the tape from the idler pulley. The inside
center should be pre-greased. If dry, regrease to
ensure proper operation.
• Place the idler pulley into the window as shown.
• Insert the idler bolt from the top through the rail
and pulley. Tighten with a 3/8" tock washer and nut
underneath the rail until the lock washer is
compressed.
• Rotate the pulley to be sure it spins freely.
• Insert a 1/4"-20 x 1-3/4 bolt into the trolley stop
hole in the front of the rail as shown. Tighten
securely with a 1/4"-20 lock nut.
Grease
Inside Pulley
3/8" Lock Trolley Idler
Washer Pulley
0
HARDWARE SHOWN ACTUAL SIZE @ @
idler Bolt Bolt 114"-20 x 1-3/4 Lock Nut 1/4"-20 Nut 3/8" Lock Washer 3/8"
9