Install The Belt And Attach The Belt Cap Retainer - Chamberlain 248739M Owner's Manual

ASSEMBLY STEP 4
Install the Belt and Attach the Belt Cap
Retainer
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 as shown.
3. With the trolley against the screwdriver, dispense the
remainder of the belt along the rail length toward the
motor unit and around the sprocket. The sprocket teeth
must engage the belt.
4. Check to make sure the belt is not twisted. Connect
the trolley threaded shaft with the master link, as
illustrated:
• Push pins of master link bar through holes in end of
belt and trolley threaded shaft.
• 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.
5. Insert the trolley threaded shaft through the hole in the
trolley. Be sure the belt is not twisted.
6. Hold the belt at the trolley shaft as you thread the
spring nut by hand onto the shaft until fi nger tight
against the trolley. Do not use any tools.
7. Remove the screwdriver.
8. Position the belt cap retainer over the motor unit
sprocket as shown and fasten to the mounting plate
with 8x3/8" hex screws provided.
Idler Pulley
Master Link
Clip-On Spring
Master Link Cap
Retaining
Trolley
Slot
Connector
Spring Nut
To avoid possible SERIOUS INJURY to fi ngers from
moving garage door opener:
• ALWAYS keep hand clear of sprocket while operating
opener.
• Securely attach sprocket cover BEFORE operating.
HARDWARE SHOWN ACTUAL SIZE
Hex Screw 8x3/8"
Pin
Notch
Trolley Master
Threaded Link Bar
Shaft
Hole
10
Spring/Trolley Nut
Belt Cap
Retainer
Hex Screws
#8x3/8"
Motor Unit
Sprocket
Mounting
Plate