Sears 139.53971SRT Garage Door Opener User 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.
Remove the two screws 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 screw
holes. Fasten with the previously removed screws.
Align the rail assembly with the top of the motor
unit. Slide the rail end onto the U-bracket, all the
way to the steps that protrude on the top and sides
of the bracket.
HARDWARE SHOWN ACTUAL SIZE _'_'1
Bolt 1/4"-20x 1-3/4 1/#-20
To avoidseriousdamageto garagedoor opener,use
only those screwsmountedin thetop of the opener.
Screws Motor Unit
Sprocket
"U" Bracket
Bolt
I Cover
SLIDE RAIL TO STOP
ON TOP AND SIDES
OF BRACKET
Lock Nut
into Back Slots1
then Snap Tab
IntoFrontSIot
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" 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 bo?tfrom 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"-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.
Chain and
Cable
3/8"Lock
Washer_
Bolt --_
TrcJIley
St_p HoIe I
Grease _
Inside Pulley
i
Idler
Pulley
Cable Loop Idler Pulley
HARDWARE SHOWN ACTUAL SIZE
Idler B01t Bolt1/4"-20x1-3/4 L0ckNut 1/4"-20 Nut3/8" LockWasher3/8"
9