Fasten The Rail To The Motor Unit; Install The Idler Pulley - Chamberlain Whisper Drive Security+ 459950 Owner's Manual

ASSEMBLY STEP 2

Fasten the Rail to the Motor Unit

1. Insert a 1/4"-20x1-3/4" bolt into the cover protection
bolt hole on the back end of the rail as shown. Tighten
securely with a 1/4"-20 lock nut. DO NOT overtighten.
2. Remove the two bolts from the top of the motor unit.
3. Use the carton to support the front end of the rail.
4. Place the "U" bracket, fl at side down onto the motor
unit and align the bracket holes with the bolt holes.
Fasten the "U" bracket with the previously removed
bolts; DO NOT use any power tools. The use of power
tools may permanently damage the garage door
opener.
HARDWARE SHOWN ACTUAL SIZE
Lock Nut
1/4"-20
Bolt 1/4"-20x1-3/4"
ASSEMBLY STEP 3

Install the Idler Pulley

1. Lay the belt beside the rail, as shown. Grasp the
end with the hooked trolley connector and pass
approximately 12" (30 cm) of belt through the window.
Keep the ribbed side toward the rail, and allow it to
hang until Assembly Step 4.
2. Remove the tape from the idler pulley. The inside
center should be pre-greased. If dry, regrease to ensure
proper operation.
3. Place the idler pulley into the window as shown.
4. Insert the idler bolt from the top through the rail
and pulley. Tighten with a 3/8" lock washer and nut
underneath the rail until the lock washer is compressed.
5. Rotate the pulley to be sure it spins freely.
6. Locate the rail tab. The rail tab is between the idler bolt
and the trolley in the front rail section. Use a fl at head
screwdriver and lift the rail tab until the tab is vertical
(90°).
Lock Washer 3/8"
To avoid SERIOUS damage to garage door opener, use
ONLY those bolts/fasteners mounted in the top of the
opener.
Cover
Protection
Bolt Hole
Lock
Washer
3/8"
HARDWARE SHOWN ACTUAL SIZE
Nut 3/8"
9
Bolts
Bolt
"U" Bracket
Lock Nut
Rail Tab
Idler Bolt
Screwdriver
Rail
Tab
Idler Pulley
Nut 3/8"
Trolley
Connector
Idler Bolt
Sprocket
CORRECT
INCORRECT
Grease Inside Pulley