Chamberlain 1240R - 1/4HP Manual De Usuario

ASSEMBLY STEP 2

Attach the Chain Spreader
and Re-install the Chain

MODELS 1256R AND 1246R ONLY
• Line up the holes in the chain spreader with the

holes in the motor unit as shown. The slot in the
chain spreader must fit over the Rail flange
(Figure 1).

• Securely fasten the chain spreader with the

hardware provided.

• Remove the trolley threaded shaft from the trolley

by loosening the inner nut and lock washer
(Figure 2).

• Guide the chain around the selected groove in the

chain spreader (to engage either the 8-tooth
sprocket or the 6-tooth sprocket) as shown
(Figure 3).

• Continue dispensing the chain forward to the

trolley (Figure 4). Reconnect the trolley to the
trolley threaded shaft. Proceed to Assembly
Step 3 for chain tightening instructions.

Trolley

Trolley
Threaded Shaft

Outer
Nut

Rail

Inner Nut
and Washer

Chain
Spreader

#8x1"
Hex Screw

USE ONLY
THIS TYPE
AND SIZE
SCREW

Rail
Flange

Slot

Washers

Sprocket

Install Chain
In This Direction

Chain
Spreader

Figure 1

Figure 2

Figure 3

Figure 4

8-Tooth
Sprocket

6-Tooth
Sprocket

Chain
Spreader

Motor Unit
Mounting Plate

Chain
Spreader

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.

WARNING

CAUTION

WARNING