Maintenance And Inspection - Hitachi WR 12DH Instruction Manual And Safety Instructions

MAINTENANCE AND INSPECTION

CAUTION: Pull out battery before doing any inspection or maintenance.
1. Checking the condition of the socket.
A worn or deformed hex or a square-holed socket will not give an adequate tihgtness to
the fitting between the nut or anvil, consequently resulting in loss of tihgtening torque.
Pay attention to wear of a socket holes periodically, and replace with a new one if needed.
2. Check the Mounting Screws
Loose mounting screws are dangerous. Regularly inspect them and make sure they are
tight.
CAUTION: Using this power tool 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. 13)
The motor employs carbon brushes which are
consumable parts. Since and excessively worn
carbon brush can result in motor trouble, replace
the carbon brush with new ones when it becomes
worn to or near the "wear limit". In addition,
always keep carbon brushes clean and ensure that
they slide freely within the brush holders.
NOTE:
When replacing the carbon brush with a new one,
be sure to use the Hitachi Carbon Brush Code No.
999054.
5. Replacing carbon brushes
Take out the carbon brush by first removing the
brush cap and then hooking the protrusion of the
carbon brush with a flat head screw driver, etc., as
shown in Fig. 15.
When installing the carbon brush, choose the di-
rection so that the nail of the carbon brush agrees
with the contact portion outside the brush tube.
Then push it in with a finger as illustrated in Fig. 16.
Lastly, install the brush cap.
English
Wear limit
0.12" (3mm)
0.45"
(11.5mm)
Fig. 13
Nail of carbon brush
Protrusion
of carbon
brush
Fig. 14
Fig. 15
19