Install The Idler Pulley - Craftsman 139.53919D Owner's Manual

ASSEMBLY STEP 2
Fasten the Rail to the Motor Unit
• Insert a 1/4"-20xl-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. Do NOT
overtighten.
• Remove the two bolts from the top of the motor
unit.
• Place the "U" bracket, flat side down, onto the
motor unit and align the bracket hole 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.
To avoid SERIOUSdamageto garage door opener,
use ONLYthose bolts/fasteners mounted in the top of
the opener.
Motor Unit
Sprocket
Bolts
"U" Bracket
Bolt
I
Cover
Protection
Bolt Hole X
HARDWARE SHOWN ACTUAL SIZE
d ©
Lock Nut
Bolt 1/4"-20x 1-3/4" 1/4"-20
o
:\
Lock Nut
SLIDE RAILTO STOPS
ON TOP AND SIDES
OF BRACKET
Foam Packaging
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" (30.5 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. -lighten 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"-20xl-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.
Lock Washerl
3/8" 9
Bolt
Trolley
Stop Hole
Grease IJ
-_ _side Pulley
--- Idle, Pulley __
Connector _ Idler (_ Lock
Pulley i Nut
HARDWARE SHOWN ACTUAL SIZE
©
Bolt 1/4"-20xl-3/4" Lock Nut 1/4"-20 Nut 3/8" Lock Washer 3/8"