Craftsman 139.53984SRT 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:
• 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.
Toavoid possible SERIOUSINJURYto fingers from
moving garage door opener:
• ALWAYSkeep hand clear of sprocket while operating
opener.
• Securely attach sprocket cover BEFORE operating.
HARDWARE SHOWN ACTUAL SIZE
Hex Screw 8 x 3/8"
SpringEr rolley Nut
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.
7. Remove the locking pliers. /_
8. Position the belt cap retainer over the motor unit
Maste, Link •
//J/
sprocket as shown and fasten to the mounting Clip-On
S pring _}'_
///._="/
plate with 8 x 3/8" hex screws provided. Master L ink
Ca _'_ "
_ ;,_°_Y e d Mna
Trolley Uait_rar
Threaded Link Bar
Sha_
Round
Hole
Retaining
Slot
Trolley
Hex Screws
Idler Pulley Belt Cap _ #8 x 3/8"
Retainer _ Motor Unit
Sprocket
Plate
lO