Sprocket Cover - Chamberlain 3112EM FS2 Owner's Manual

ASSEMBLY STEP 5
For Sectional and One-Piece Doors Only
Install the Chain/Cable and Attach the

Sprocket Cover

1. Pull the cable loop from the
carton and fasten it to the
trolley with a master link
from the hardware bag
(Figure 1).
• Push pins of master link
bar through cable loop
and hole in front end of
trolley.
• Push master link cap over pins and past pin notches.
• Slide clip-on spring over cap and onto pin notches
until both pins are securely locked in place.
2. With the trolley against the screwdriver, dispense the
cable around the pulley.
3. Model 3112EM:
• Continue along the rail and around the motor unit
sprocket (Figure 2). The sprocket teeth must engage
the chain. Continue forward to the trolley threaded
shaft.
Model 3122EM:
• Continue along the rail and around the motor unit
sprocket (Figure 2). Proceed back around the correct
groove in the chain spreader (Figure 3). The sprocket
teeth must engage the chain.
4. Use the second master link to connect the chain to the
flat end of the shaft (Figure 1). Check to make sure
the chain is not twisted.
5. Remove the screwdriver.
ATTACHING THE SPROCKET COVER
3112EM ONLY
Insert the back tab in the slot on the back of the
mounting plate. Squeeze the cover slightly and insert the
front tab (Figure 4).
Figure 4
Front Tab Slot
Leave Chain
& Cable
Inside Carton to
Prevent Kinking.
Keep Chain & Cable
Taut When Dispensing
Sprocket
Cover
Back Tab Slot
Top of Motor Unit
Mounting
Plate
To avoid possible SERIOUS INJURY to fingers from moving
garage door opener:
• ALWAYS keep hand clear of sprocket while operating opener.
• Securely attach sprocket cover BEFORE operating.
Figure 1
Master Link
Clip-On Spring
Master Link Cap
Cable
Loop
Cable
Pulley
Install Chain & Cable
In This Direction
Figure 2
Figure 3
Chain
Spreader
6-Tooth Sprocket Application (Model 3122EM)
Chain
Spreader
8-Tooth Sprocket Application (Model 3122EM)
(6-tooth sprocket can be used if slower travel speed is
13
Master Link
Clip-On Spring
Master
Link Cap
Flat end
of Trolley
Threaded
Shaft
Master
Link Bar
Install Chain
Chain
In This Direction
Spreader
Motor Unit
Sprocket
6-Tooth
Sprocket
Mounting
Plate
One-Piece Doors
8-Tooth
Sprocket
Mounting
Plate
Sectional Doors
desired.)
Chain
Pin
Notch
Pin