Craftsman 139.53335SRT3 Garage Door Opener User Manual


 
Installation Step 4
Position the Opener
Follow instructions which apply to your door
type as illustrated.
CAUTION
To prevent damage to steel, aluminum,
fiberglass or glass panel doors, do not rest the
opener on the door without using a 2x4.
SECTIONAL Door & ONE-PIECE Door with Track I
A 2x4 laid flat is convenient for setting an ideal
door-to-T-rail distance.
Raise the opener onto a stepladder.
You will need help at this point if the ladder is
not tall enough,
Open the door all the way and place a 2x4 laid flat
on the top section beneath the T-rail.
if the top panel hits the trolley when you raise
the door, pull down on the trolley release arm to
disconnect the inner and outer sections. The
trolley can remain disconnected until Step 12 is
completed,
T-rail 2x4
Door
Stepladder
Trol_se Arm
With the door fully open and parallel to the floor,
measure the distance from the floor to the top of
the door.
Using a stepladder as a support, raise the opener
to the same distance as the door from the floor (it
will be at a slight angle as shown).
The top of the door should be level with the top of
the opener. Do not position the opener more than
2" above this point.
Header
Bracket
I
Top of Opener
Stepladder
16