English
MAINTENANCE AND INSPECTION
WARNING: Be sure to switch power OFF and disconnect the plug from the receptacle during maintenance and inspection.
1.Inspecting the drill bits
Since use of a dull tool will cause motor malfunctioning and degraded efficiency, replace the drill bit with a new one or resharpening without delay when abrasion is noted.
2.Inspecting the screws
Regularly inspect all screws and ensure that they are properly tightened. Should any of the screws be loose, retighten them immediately.
WARNING: Using this Rotary Hammer with loosen screws is extremely dangerous.
3.Maintenance of the motor
The motor unit winding is the very “heart” of the power tool. Exercise due care to ensure the winding does not become damaged and/or wet with oil or water.
4.Inspecting the carbon brushes: (Fig. 20)
The motor employs carbon brushes which are consumable parts. When they become worn to or near “wear limit”, it could result in motor trouble. When an
In addition, always keep carbon brushes clean and ensure that they slide freely within the brush holders.
CAUTION: Using this Rotary Hammer with a carbon brush which is worn in excess of the wear limit will damage the motor.
Wear limit
No. of carbon brush
73
0.28" (7 mm)
0.67" (17 mm)
Fig. 20
NOTE: Use HITACHI carbon brush No.73 indicated in Fig. 20
◯Replacing carbon brushes: (For parts name, refer to Fig. 1)
Loosen the two set screws and remove the tail cover. Remove the brush caps and carbon brushes. After replacing the carbon brushes, tighten the brush caps securely and to install the tail cover with securely tightening two set screws.
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