Hitachi DH 25DL Technical Data And Service Manual page 22

Removal of the cylinder and the second hammer
Hammer Holder [32]
Second Hammer [30]
Vise
6. Removal of the armature and the housing
After disassembly of the hammering mechanism section, remove the Machine Screw M4 x 8 [87] from the
Grip Cover [86] and remove the Grip Cover [86] to show the carbon brushes. Hook the Spring [65] on the
edge of the carbon brush tube. Remove the Tapping Screw (W/Flange) D4 x 16 (Black) [58] from the Inner
Cover Ass'y [43]. Then the Inner Cover Ass'y [43] can be removed together with the Armature and Pinion
Ass'y [61]. At this time, be careful not to damage the carbon brushes. The Inner Cover Ass'y [43] and the
Armature and Pinion Ass'y [61] can be removed just by pressing the Pinion [56] slightly with a press
because there is an interference of the O-ring (P-22) [59]. The housing is constructed of two parts. Remove
the Tapping Screw (W/Flange) D4 x 20 (Black) [69] to disassemble the housing.
7. Removal of the carbon brush holder
After disassembly of the housing, remove the Tapping Screw (W/Flange) D4 x 16 (Black) [58] to remove
the carbon brush holder.
8. Replacement of the carbon brushes
Remove the Grip Cover [86] to show the carbon brushes. Pinch the terminal of the Carbon Brush (Auto
Stop Type) (1 Pair) [67] with a pair of long-nose pliers and pull it out of the carbon brush holder. At this time,
melt solder at the terminal. Hook the Spring [65] on the Carbon Brush (Auto Stop Type) (1 Pair) [67] with a
flat-blade screwdriver and remove the Carbon Brush (Auto Stop Type) (1 Pair) [67].
Replacement of the carbon brushes
Tap with a hammer.
O-ring (1AP-20) [31]
Damper (A) [34]
O-ring (B) [33]
Long-nose pliers
Punch (C) (J-341)
5-mm diameter hole (2 pcs.)
Damper Holder [36]
O-ring (C) [35]
Stopper Ring [37]
Stopper ring jig (A) (J-341)
Terminal
Carbon
Brush (Auto
Stop Type)
(1 Pair) [67]
-19-
Spring [65]
Flat-blade
screwdriver