Craftsman 139.53993D Garage Door Opener User Manual


 
ASSEMBLY STEP 2
Fasten the Rail to the Motor Unit and
Install the Trolley
NOTE: To aid in assembly and installation, replace the
foam packing around the motor unit. Remove it after
Installation Step 4.
1. Working on a level surface, align the rail assembly with
the motor unit, as shown.
2. Slip the coupling over the rail sprocket.
3. Slide the rail through the motor unit bracket until the
coupling fits securely over the motor unit sprocket.
4. Align the four bolt holes in the rail with those in the
motor unit bracket. Insert four 1/4"-20x7/16" hex bolts.
Tighten securely with a 3/8" socket wrench.
5. Disengage trolley by turning the release arm down
(arrow pointing up). Slide trolley onto and along the
bottom of the rail until it aligns with the rack. Turn
release arm up (arrow pointing away from motor unit.
This will join the rack and the trolley.
Coupling
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Hex Bolts
1/4-20x7/16"
HARDWARE SHOWN ACTUAL SIZE
Hex bolt 1/4-20x7/16"
Motor Unit
Bracket
Motor Unit
Sprocket
Hex Bolts
1/4-20x7/16"
Foam Packaging
Trolley -
10