Craftsman 139.53964SRT Owner's Manual page 10

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 pliers, 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, then
connect it to the flat end of the trolley threaded
shaft with the master link, as illustrated:
Toavoid possible SERIOUSINJURYto fingers from
moving garage door opener:
• ALWAYSkeep hand clear of sprocket while operating
opener.
• Securely attach sprocket cover BEFORE operating.
• 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, and
the ribbed side faces the rail.
6. Hold the belt at the trolley shaft as you thread the
spring nut by hand onto the shaft until finger tight
against the trolley. Do not use any tools.
HARDWARE SHOWN ACTUAL SIZE
Hex Screw 8 x 3/8"
Spring/Trolley Nut
7. Remove the locking pliers. /___
8. Position the belt cap retainer over the motor unit /_/j/
• Master Link .
sprocket as shown and fasten to the mounting Cli On
_
rin
"_ /_/_'/
•
.
p- bp g
plate with 8 x 3/8" hex screws provided. __
Master Link Cap _- /.. "
Pin
Trolley Master
Threaded
Link Bar
Shaft
Round
Hole
Retaining
Troltey Slot
_Hex Screws
Idler Pulley Belt Cap _ #8 x 3/8"
Retainer _ Motor Unit
J Sprocket
_Spdng Nut
10