Hitachi DH 24PD3 Technical Data And Service Manual page 28

(6) Disassembly of the cylinder and the second hammer
Remove the Stopper Ring [35] from the inside diameter portion of the Cylinder [18]. Then the Second
Hammer [28], O-ring (1AP-20) [29], Damper Holder [30], O-ring (B) [31], Damper (A) [32], O-ring (C) [33] and
Hammer Holder [34] can be removed from the Cylinder [18]. As shown in Fig. 18, insert stopper ring jig (A)
(J-341) into the no-hole side of the Cylinder [18] until it contacts the end surface of the Hammer Holder [34].
Hold the Cylinder [18] and the end surface of stopper ring jig (A) (J-341) with a vise, and compress Damper
(A) [32] (it moves a little when the Stopper Ring [35] is pressed with punch (C) (J-341)). Insert punch (C) (J-
341) into the 5-mm diameter hole (2 places) in the Cylinder [18] and tap the outside of the Stopper Ring [35]
until the Stopper Ring [35] cannot be seen from the 5-mm diameter hole (2 places) to remove the Stopper
Ring [35] from the groove of the inside diameter portion of the Cylinder [18]. Then remove the Cylinder [18]
from the vise and pull out the Stopper Ring [35] from the inside diameter portion of the Cylinder [18] with ring
puller jig (B) (J-341) being careful not to pop out the Stopper Ring [35]. At reassembly, replace the Stopper
Ring [35] with new one as the removed Stopper Ring [35] is deformed. To prevent idle hammering, also
replace O-ring (C) [33] with new one at reassembly.
Tap with a hammer.
Punch (C) (J-341)
5-mm diameter hole (2 pcs.)
O-ring (1AP-20) [29]
Hammer Holder [34]
Damper Holder [30]
O-ring (C) [33]
Second Hammer [28]
Vise
Vise
O-ring (B) [31]
Damper (A) [32]
Stopper Ring [35]
Stopper ring jig (A) (J-341)
Fig. 18
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