Chamberlain HD920EV Owner's Manual page 9

Assembly
STEP 4 Install the belt
1. Pull the belt around the idler pulley and toward the trolley. The ribbed side must contact the
pulley.
2. Hook the trolley connector into the retaining slot on the trolley. (a)
3. With the trolley against the screwdriver, dispense the remainder of the belt along the rail
toward the motor unit around the sprocket. The sprocket teeth must engage the belt. (b)
4. Thread the inner nut and lock washer onto the trolley thread shaft (c). Check to make sure the
belt is not twisted.
5. Insert the trolley threaded shaft through the hole in the trolley. Be sure the belt is not
twisted. (c)
6. Loosely thread the outer nut onto the trolley threaded shaft.
7. Remove the screwdriver.
a.
Trolley Connector
Retaining Slot
c.
Front Rail
Section
(TO DOOR)
8
b.
Sprocket
Inner
Nut
Lock
Outer
Washer
Nut
Threaded
Shaft
Idler
Pulley