Справочник Пользователя для Chamberlain WD912K

10

1. Drop the notched side of the trolley clip into the

retaining slot on top of the trolley (Figure 1).

2. Grasp the clip connector at the end

of the belt and slip it through the belt
pulley bracket from behind, around
the pulley and toward the trolley.

3. Fasten the belt clip connector to the

trolley clip with a master link:

• Push pins of master link bar

through holes in trolley clip and belt
clip connector. 

• 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.

4. With the trolley against the screwdriver,

dispense the belt along the rail and around
the motor unit sprocket. The sprocket teeth
must engage the belt (Figure 2).

5. Use the second master link to connect the belt

to the flat end of the trolley threaded shaft
(Figure 1). Check to make sure the belt is not
twisted.

6. Remove the screwdriver.

1. Insert the trolley threaded shaft through the hole in

the trolley.

2. Hold the belt at the trolley shaft to avoid twisting as

you thread the spring/trolley nut by hand on the
shaft until finger tight against the trolley (Figure 3).
Do not use any tools.

3. Insert a screwdriver tip into one of the nut ring

slots and brace it firmly against the trolley.
(Figure 4). 

4. 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 5).

This extends the spring for optimum belt tension.

Nut
Ring

Trolley
Threaded 
Shaft

Nut Ring
Slots

Square 
End

Motor unit
Sprocket

Belt
Pulley

Slip Belt Clip 
Connector around 
Pulley Bracket
from this direction
and attach to trolley clip 

Trolley
Clip

Master Link
Clip-On Spring

Master
Link Cap

Trolley
Threaded Shaft

Master
Link Bar

Master
Link Bar

Pin Notch

Pin Notch

Belt
Clip Connector

Belt Clip 

Connector

Trolley
Threaded
Shaft

Spring/Trolley Nut

Nut Ring

Trolley

Nut Ring

Trolley

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.