Fasten The Rail To The Motor Unit And Install The Idler Pulley - Craftsman 139.53997D Owner's Manual

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 bolt holes. Fasten with the previously
removed bolt 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.
HARDWARE SHOWN ACTUAL SIZE
Lock Nut 1/4"-20
Washer 5/8"
Bolt 1/4"-20x2-1/2
ASSEMBLY STEP 3
Install the Idler Pulley
• Lay the chain/cable beside the rail, as shown.
Grasp the end of the cable 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.
Idler Bolt
To avoid SERIOUS damage to garage door opener,
use ONLY those bolts/fasteners mounted in the top of
the opener.
Bolt
Washer
Spacer
Cover
Protection
Bolt Hole
Spacer
Spacer
Chain and
Cable
Idler
Bolt
Lock
Washer
3/8"
HARDWARE SHOWN ACTUAL SIZE
Bolt 1/4"-20x1-3/4"
9
WARNING
CAUTION
Hex Screws
8-32x7/16"
Bolt
Lock Nut
"U" Bracket
SLIDE RAIL TO STOPS
ON TOP AND SIDES
Washer
OF BRACKET
Lock Nut
Bolt
Pulley
Washer
Trolley
Screwdriver
Grease
Inside Pulley
Idler
Pulley
Nut 3/8"
Cable Link
Lock Nut 1/4"-20 Nut 3/8"
Chain
Spreader
Motor Unit
Sprocket
Rail
Nut
Bolt
Trolley
Stop Hole
Lock
Idler
Nut
Pulley
Lock Washer 3/8"