Fasten the rail to the motor unit, Install the idler pulley, Warning caution warning warning – Craftsman 139.5399 User Manual
Page 9: Assembly step 2, Assembly step 3
9
To avoid SERIOUS damage to garage door opener,
use ONLY those bolts/fasteners mounted in the top of
the opener.
ASSEMBLY STEP 2
Fasten the Rail to the Motor Unit
• Insert a 1/4"-20x2-1/2 bolt, washer and spacer into
the cover protection bolt hole on the back end of
the rail as shown. Install lower spacer and washer
then tighten securely with a 1/4"-20 lock nut.
Do NOT overtighten.
• Remove the bolt and lock nut from the top of the
motor unit.
• Attach spreader to the motor unit with two screws.
• Place the U bracket, flat side down onto the bolt,
mounted on the motor unit and align the bracket
hole with the screw hole. Fasten with the
previously removed screw and lock nut.
• 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.
ASSEMBLY STEP 3
Install the Idler Pulley
• Lay the chain/cable beside the rail, as shown.
Grasp the end with the cable loop and pass
approximately 12" (30 cm) of cable through the
window. 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" lock 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"-20x1-3/4 bolt into the trolley stop hole
in the front of the rail as shown. Tighten securely
with a 1/4"-20 lock nut.
WARNING
CAUTION
WARNING
WARNING
Bolt
Hex Screws
8-32x7/16
Chain
Spreader
Motor Unit
Sprocket
"U" Bracket
Lock Nut
Lock Nut
SLIDE RAIL TO STOPS
ON TOP AND SIDES
OF BRACKET
Cover
Protection
Bolt Hole
Bolt
Spacer
Spacer
Washer
Washer
Idler
Pulley
Grease
Inside Pulley
3/8" Lock
Washer
3/8" Nut
Cable Loop
Idler
Bolt
Locking Pliers
Trolley
Stop Hole
Chain and
Cable
Pulley
Rail
Bolt
Nut
Washer
Trolley
Idler Pulley
Trolley
Stop Hole
Bolt
Bolt 1/4"-20 x 2-1/2
Spacer
Washer 5/8"
HARDWARE SHOWN ACTUAL SIZE
Nut 3/8"
Lock Washer 3/8"
Lock Nut 1/4"-20
Idler Bolt
Bolt 1/4"-20 x 1-3/4 (1)
HARDWARE SHOWN ACTUAL SIZE