Repair Guide; Precautions And Suggestions For Disassembly And Reassembly Of The Main Body - Hitachi H 90SE Technical Data And Service Manual

9. REPAIR GUIDE

9-1. Precautions and Suggestions for Disassembly and Reassembly of the Main Body

The [Bold] numbers in the descriptions below correspond to the item numbers in the Parts List and exploded
assembly diagram.
9-1-1. Disassembly
[NOTE] If it is difficult to loosen and remove the fixing bolts, use an appropriate heating device to heat them to
approximately 80 ˚C (176 ˚F).
Disassembly of the Armature Ass'y [99]
(1) Remove the two Seal Lock Hex. Socket Hd. Bolts M4 x 10 [89], and disassemble the Cap Cover [90] and the
Carbon Brushes [92].
(2) Loosen the Lock Nut M8 (Nylon Insert) [48], and remove the Washer M8 [47]. Then, while pressing on the
Switch Handle side, pull the Side Handle [55] and Handle Holder (A) [56] from the Handle Shaft [51]. Next,
pull off the Switch Handle side and gently tap the end of the Handle Shaft [51] on one side to loosen and
remove the Holder (A) [53] and Handle Dampers [54] (4 pcs.) from one side. The Handle Shaft [51] can then
be extracted from the Housing Ass'y [85].
(3) Remove the four Seal Lock Hex. Socket Hd. Bolts M10 x 60 [58] and two Seal Lock Hex. Socket Hd. Bolts
M10 x 55 [66] and take off the Gear Cover Ass'y [59]. At the same time, also remove the First Gear [68] and
Second Gear [69]. Next, by inserting a flat-blade screwdriver or similar tool into one of the air vents of the
Inner Cover [76] and lifting it upwards, the Inner Cover [76], Armature Ass'y [99], Crank Shaft [84], and
connected parts can be removed in a single body.
(4) As illustrated in Fig. 13, support the Inner Cover [76] with an appropriate tubular jig (100 mm inner dia.), and
push down on the pinion end of the Armature Ass'y [99] with an arbor press to separate the Armature Ass'y
from the Inner Cover [76]. At this time, be very careful not to lose the Bearing Washer [74] which is mounted
on the fan ass'y portion of the Armature Ass'y.
Inner Cover [76]
Crank Shaft [84]
Push
100 mm
Fig. 13
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Bearing Washer [74]
Armature Ass'y [99]
Tubular Jig