Assembly - Chamberlain 85870 Manual

Assembly

1 Attach the Rail to the Garage Door Opener
To avoid SERIOUS damage to garage door opener, use ONLY those bolts/fasteners mounted in
the top of the opener.
NOTE: ONLY use the bolts removed from the garage door opener. Place the garage door opener on
the packing material to prevent scratching.
1. Remove bolt and lock nut from the top of the garage door opener.
2. Align the rail and the styrofoam over the sprocket. Cut the tape from the rail, chain, and
styrofoam.
3. Fasten the rail with the previously removed washered bolt and lock nut.
4. Position the chain around the garage door opener sprocket.
5. Attach the chain spreader to the garage door opener with screws.
6. Guide the chain around the selected groove in the chain spreader, to engage either the 8-
tooth or 6-tooth sprocket.
NOTE: The 6-tooth sprocket is for use with Carriage House Doors and the 8-tooth sprocket
is for use with regular doors.
HARDWARE
Washered Bolt
5/16"-18x1/2"
(Mounted in the garage
door opener)
Model 85870 only
Chain Spreader
Motor Unit Mounting Plate
7
Lock Nut
(Mounted in the
garage door opener)
Hex Screws 8-32x1"
Washered Bolt
5/16"-18x1/2"
Washers
Lock
Nut
6-Tooth Chain Spreader 8-Tooth
Sprocket Sprocket
Motor Unit Mounting Plate