Precautions In Disassembly And Reassembly; Disassembly; Reassembly - Hitachi C 7YA Technical And Service Manual

8. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY

Disassembly and reassembly procedures which require particular precautions are described below.
The [Bold] numbers in the descriptions below and the circled numbers in the following figures correspond to the
item numbers in the Parts List and the exploded assembly diagram for the Model C 7YA.
Be sure to unplug the Model C 7YA from the wall outlet before performing disassembly or replacement of the saw
blade.

8-1. Disassembly

(1) Prior to attempting further disassembly, ensure without fail that the Saw Blade is removed to prevent damage
to its cutting edge, and to avoid possible serious accident.
(2) Remove the Safety Cover [8]:
First, disconnect the Return Spring [9]. Then, loosen the two Seal Lock Flat Hd. Screws M4 x 10 [13], and
take off the Bearing Cover [12]. The Safety Cover [8] can then be removed.
(3) Remove the Bearing Holder [3] together with the Spindle and Gear Set [2]:
After removing the Safety Cover [8] as described above, loosen the two Seal Lock Flat Hd. Screws M5 x 14
[4], and take off the Bearing Holder [3] together with the Spindle and Gear Set [2].
(4) Separate the Spindle and Gear Set [2] from the Bearing Holder [3]:
As illustrated in Fig. 1, support the Bearing Holder [3]
with an appropriate tubular jig, and push down on the end
of the Spindle and Gear Set [2] with a hand press to separate
the Spindle and Gear Set [2] from the Bearing Holder [3].
(5) Remove the Armature Ass'y [31]:
First, remove the Carbon Brushes [42]. Next, take off the
Clamp Lever [68], loosen the Clamp Nut [70], and remove the
Bolt (Square) M6 x 20 [52]. Then, loosen the Machine Screws (W/Washers) M5 x 45 [22], and separate the
Housing Ass'y [23] from the Gear Cover [36]. The Armature Ass'y [31] will remain within the Housing Ass'y
[23]. With a wooden or plastic hammer, tap gently on the outside of the Housing Ass'y [23] to loosen and
remove the Armature Ass'y [31]. At this time, be very careful not to hit the fan on the Armature Ass'y [31].
(6) Remove the Base Ass'y [63]
Extract the Roll Pin D6 x 40 [64] which connects the Base Ass'y [63] and the Housing Ass'y [23], and separate
them.

8-2. Reassembly

Reassembly can be accomplished by following the disassembly procedures in reverse. However, particular
attention should be given to the following items.
(1) Tightening torque for fastening screws:
M4 Machine Screws
M5 Machine Screws
M8 x 15.5 Flange Bolt [16]
D4 Tapping Screws
D5 Tapping Screws
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14 to 24 kg•cm (12 to 21 in-lbs.)
28 to 50 kg•cm (24 to 43 in-lbs.)
80 to 120 kg•cm (70 to 105 in-lbs.)
15 to 25 kg•cm (13 to 22 in-lbs.)
25 to 35 kg•cm (22 to 30 in-lbs.)
--- 7 ---
Push
Jig
49 mm
(1-15/16")
Fig. 1