Care And Maintenance - Kobalt 6904 Manual

OperatinG inStrUctiOnS
2. Turn the tool on, and fasten the bolt or nut to the proper torque.
3. After fastening, always check the torque with a torque wrench.
nOte: Hold the tool straight along the axis of the bolt or nut.
nOte: Excessive fastening torque may damage the bolt/nut or socket.
Practice with various fasteners, noting the length of time required to reach the desired torque.
Check the tightness with a torque wrench. If the fasteners are too tight, reduce the impacting time.
If they are not tight enough, increase the impacting time.
The fastening torque is affected by a wide variety of factors, including the following:
• Voltage
A voltage reduction will cause a reduction in the fastening torque.
• Socket
Failure to use the correct size socket will cause a reduction in the fastening torque.
A worn socket (wear on the hex end or square end) will cause a reduction in the fastening torque.
• Bolt
Although the torque coefficient and the class of bolt may be the same, the proper fastening torque
will differ according to the diameter of the bolt.
Although the diameters of bolts may be the same, the proper fastening torque will differ according
to the torque coefficient, the class of bolt and the bolt length.
• The use of a universal joint or an extension bar (both available separately) will reduce the
fastening force of the impact wrench somewhat. Compensate by fastening for a longer period of
time.
• The manner of holding the tool or the material to be fastened will affect the torque.
Loosening fasteners with the impact wrench
The torque that is required to loosen a fastener averages 75% to 80% of the tightening torque,
depending on the condition of the contacting surfaces. However, if rust or corrosion causes seizing,
more torque may be required.

care anD maintenance

warninG: To ensure safety and reliability, all repairs should be performed by a qualified
service technician.
warninG: When servicing, use only identical replacement parts. The use of any other parts
may create a hazard or cause damage to the product.
warninG: Unplug the impact wrench from the power source before cleaning or performing any
maintenance.
Before each use:
• Inspect the impact wrench, the switch, and the cord for damage.
• Check for damaged, missing, or worn parts.
• Check for loose screws, misalignment or binding of moving parts, or any other condition that may
affect the operation.
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