Sears 139.53971SRT owner manual Assemble the Rail & Install the Trolley, Back Rails, To Motor Unit

ASSEMBLY STEP 1

Assemble the Rail & Install the Trolley

To avoid installation difficulties, do not run the garage door opener until instructed to do so,

The front rail has a cut out "window" at the door end (see illustration). The hole above this window Is larger on the top of the rail than on the bottom. A smaller hole 3-112" away is close to the rail edge. Rotate the back rail so it has a similar ho/e close to

the opposite edge, about 4-314" from the far end. A 3-piece rail uses two back rails.

1.Remove the straight door arm and clevis pin packaged inside the front rail and set aside for Installation Step 12.

2.Align the rail sections on a flat surface exactly as shown and slide the tapered ends into the larger

ones. Tabs along the side will lock into place.

3.Place the motor unit on packing material to protect the cover, and rest the back end of the rail on top.

For convenience, put a support under the front end of the rail.

4.As a temporary trolley stop, clamp a locking pliers onto the rail, 8" from the center of the idler pulley hole, as shown.

5.Check to be sure there are 4 black plastic wear pads inside the inner trolley. If they became loose during shipping, check all packing material. Snap them back into position as shown.

6.Connect the inner and outer trolleys as shown.

7.Slide the trolley assembly along the rail from the back end to the locked pliers.

Trolley

End

Back Rails

(TO MOTOR UNIT)

Inner TrolLey

Wear Pads

8