A warning, Assembly step 4 – Sears 139.53971SRT User Manual
Page 10
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ASSEMBLY STEP 4
Instali the Chain/Cable
and Attach the Sprocket Cover
1. Pul! the cable around the idler pulley and toward
the trolley.
2. Connect the cable loop to the retaining slot on the
trolley, as shown:
• From below, push pins of master link bar up
through cable loop and trolley slot.
• 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.
3. With the trolley against the pliers, dispense the
remainder of the cable/chain along the rail toward
the motor unit and around the sprocket. The
sprocket teeth must engage the chain.
4. Check to make sure the chain is not twisted, then
connect it to the threaded shaft with the
remaining master link.
5. Thread the inner nut and lock washer onto the the
trolley shaft,
6. Insert the trolley threaded shaft through the hole
in the trolley. Be sure the chain is not twisted.
7. Loosely thread the outer nut onto the trolley shaft.
8. Remove the locking pliers.
9. Align the tabs on the sprocket cover with the slots
in the mounting plate. Squeeze cover and insert
tabs in slots.
A WARNING
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.
Dispensing Carton
Taut When Dispensing
Mastef Link
Clip-On Spring
Idler
Pulley
Cable
- Master
Link Bar
Master
Link Bar
Sprocket pr- ■
Cover—
Front
Tab Slot
Mounting
Plate
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