Tighten The Chain; Installation - Craftsman 139.53930DM Owner's Manual

ASSEMBLY STEP 5
Tighten the Chain
• Spin the inner nut and lock washer down the trolley
threaded shaft, away from the trolley.
• To tighten the chain, turn outer nut in the direction
shown (Figure 1).
• When the chain is approximately 1/4" (6 mm) above the
base of the rail at its midpoint, re-tighten the inner nut to
secure the adjustment.
Sprocket noise can result if chain is too loose.
When installation is complete, you may notice some chain
droop with the door closed. This is normal. If the chain
returns to the position shown in Figure 2 when the door is
open, do not re-adjust the chain.
NOTE: During future maintenance, ALWAYS pull the
emergency release handle to disconnect trolley before
adjusting chain. You may notice loosening of chain after
Adjustment Step 3 (Test the Safety Reversal System).
Check for proper tension and readjust chain if necessary.
Then repeat Adjustment Step 3.
You have now finished assembling your garage door
opener. Please read the following warnings before
proceeding to the installation section.
Figure 1 Trolley
Outer Lock Threaded
Nut Washer Shaft
To Tighten Outer Nut ==='_l _ i /
Figure 2
Chain
mm--;--
I
Base of Raft Mid bength of RaiJ
INSTALLATION
IMPORTANT INSTALLATION INSTRUCTIONS
To reduce the risk of SEVERE INJURY or DEATH:
1. READAND FOLLOWALL INSTALLATIONWARNINGS
AND iNSTRUCTiONS.
2. Install garage door opener ONLYon properly balanced
and lubricated garage door. An improperly balanced
door may not reverse when required and could result in
SEVEREINJURYor DEATH.
3. ALL repairs to cables, spring assemblies and other
hardware MUST be made by a trained door systems
technician BEFORE installing opener.
4. Disable ALL locks and remove ALL ropes connected to
garage door BEFORE installing opener to avoid
entanglement.
5. Install garage door opener 7 feet (2.13 m) or more
above floor.
6. Mount emergency releasehandle 6 feet (1.83 m) above
floor.
7. NEVERconnect garage door opener to power source
until instructed to do so.
8. NEVERwear watches, rings or loose clothing while
installing or servicing opener. They could be caught in
garage door or opener mechanisms.
9. Install wall-mounted garage door control:
• within sight of the garage door.
• out of reach of children at minimum height of 5 feet
(1.5 m).
• away from ALL moving parts of the door.
10. Placeentrapment warning label on wall next to garage
door control.
11. Placemanual release/safety reversetest label in plain
view on inside of garage door.
12. Upon completion of installation, test safety reversal
system. Door MUST reverse on contact with a
1-1/2" (3.8 cm) high object (or a 2x4 laid flat) on
the floor.
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