Chamberlain 7920KD User Manual

Cable

Chain

Motor Unit
Sprocket

A2
Chain and
Cable in
Dispensing
Carton

Leave chain/cable inside
carton to prevent kinking

Master Link
Clip-On Spring

Trolley
Threaded
Shaft

Master
Link Bar

Attach Chain To Trolley
Threaded Shaft

Trolley
Threaded
Shaft

Lock Washer

Outer Nut

Insert Trolley Threaded
Shaft into Round Hole in
Trolley

Trolley
Threaded
Shaft

Inner Nut

Lock
Washer

Attach Nut and Lock
Washer to Trolley
Threaded Shaft

Tighten the Chain

Base of Rail

Mid Length of Rail

Chain

1/4" (6 mm)

Desired Chain Tension

Master Link

Nut

Lock Washer

Threaded Trolley Shaft

ALL HARDWARE SHOWN ACTUAL SIZE

To avoid possible SERIOUS INJURY to fingers:
• Securely attach chain spreader.
• NEVER connect garage door opener to power source until

instructed to do so.

WARNING

CAUTION

WARNING

Route Chain/Cable Around Rail Assembly
and Motor Unit Sprocket

Assembly of your opener is now complete.