Chamberlain 3585 3/4 HP Garage Door Opener User Manual


 
To avoid SERIOUS damage to opener, ONLY use
bolts/fasteners mounted in top of motor unit.
WARNING
CAUTION
WARNING
WARNING
ASSEMBLY STEP 1
Attach the Rail to the Motor Unit
To avoid installation difficulties, do not run the
garage door opener until instructed to do so.
Remove the bolt and lock nut from the top of the
motor unit.
Place rail onto the bolt mounted on the motor unit
and align the back hole with the hole in the top of
the unit.
Fasten rail with the washered bolt and lock nut
previously removed. Tighten securely. Remember
to use only these bolts/fasteners! Any other
bolts/fasteners will cause serious damage to
the opener.
Cut tape from rail, belt and styrofoam.
REMOVE STYROFOAM.
• Position belt over the motor unit sprocket.
Motor unit
Sprocket
Washered Bolt
5/16"-18x1/2"
Styrofoam
Rail
Hole
Lock Nut
6
ASSEMBLY STEP 2
Set the Belt Tension
By hand, thread the spring trolley nut on the
threaded shaft until it is finger tight against the
trolley (Figure 1). Do not use any tools.
Insert a screwdriver tip into one of the nut ring
slots and brace it firmly against the trolley
(Figure 2).
Place a 7/16" open end wrench on the square
end. Rotate about 1/4 turn until the spring releases
and snaps the nut ring against the trolley
(Figure 3).
This extends the spring for optimum belt tension.
Trolley
Threaded
Shaft
Spring/Trolley Nut
Nut
Ring
Trolley
Threaded
Shaft
Nut Ring
Slots
Square
End
Nut Ring Trolley
Nut Ring
Trolley
1" (2.5 cm) 1-1/4" (3.18 cm)
BEFORE AFTER RELEASE
Figure 1
Figure 2Figure 3