Hitachi DH 18DPA Service Manual page 3

2. Disassembly of the hammering mechanism
(1) Removal of the gear cover
Set the Change Lever [11]{11} to the "Rotation + Hammering" (
Tapping Screws (W/Flange) D4 x 30 (Black) [8]{8} to remove the Gear Cover [9]{9}.
(2) Disassembly of inner cover (B) ass'y
Remove the two Seal Lock Hex. Socket Hd. Bolts M5 x 14 [34]{34} from Inner Cover (B) [35]{35}.
Remove the assembly of the Piston [31]{31} and Second Shaft (A) [43]{43} from Inner Cover (A) Ass'y
[49]{49}.
NOTE: The Seal Lock Hex. Socket Hd. Bolt M5 x 14 [34]{34} loses its bonding force if removed.
Use the new Seal Lock Hex. Socket Hd. Bolt M5 x 14 [34]{34} at reassembly.
Fig. 2 • Disassembly of inner cover (B) ass'y
[49]{49}
(3) Disassembly of second shaft (A) ass'y
Engage the claw of the Clutch [44]{44} with the claw of the Reciprocating Bearing [45]{45} and place
the Clutch [44]{44} on a cradle as shown in Fig. 3. Push the rear end of Second Shaft (A) [43]{43} with
a hand press to push out the Bevel Gear [48]{48} from Second Shaft (A) [43]{43}. Then, remove Thrust
Washer (C) [47]{47}, Reciprocating Bearing [45]{45}, Needle Cage [46]{46}, and Clutch [44]{44} from
Second Shaft (A) [43]{43}.
Fig. 3 • Disassembly of second shaft (A) ass'y
Hand press
[31]{31}
[47]{47}
[48]{48}
[43]{43}
[46]{46}
-2-
mark) position. Remove the four
[35]{35}
[43]{43}
[45]{45}
[44]{44}