Hitachi DH 40MR Technical And Service Manual page 25

(4) Reassembly of the slip clutch
Press-fit the Bevel Pinion [50] into the Collar [51] and the Ball Bearing 6002DDCMPS2L [53] then insert it into
the Washer [54] and Washer (A) [55]. Mount the Feather Key 3 x 3 x 8 [44] to the Bevel Pinion [50] then
press-fit into the Gear Holder [56]. Mount the Second Gear [59] around the outer circumference of the Gear
Holder [56]. Before mounting, apply Hitachi Motor Grease No. 29 to the inner circumference of the Second
Gear [59]. Insert the ten Needles [58] being careful not to incline them, then push in ten Springs (C) [57] as
shown in Fig. 23. Fill the slots and the through holes of the Gear Holder [56] with Hitachi Motor Grease No.
29. Press-fit the Bevel Pinion [50] into the Spacer [60] and the Ball Bearing 629VVC2PS2L [61].
Bevel Pinion [50]
Washer (A) [55]
Gear Holder [56]
Second Gear [59]
Ball Bearing
629VVC2PS2L [61]
(5) Carbon brush inspection
The motor employs Carbon Brushes [91] which are
consumable parts. When they become worn to or
near "wear limit" (7 mm), it could result in motor
trouble. Replace the Carbon Brushes [91] with new
ones which are numbered "73" as shown in Fig. 24.
In addition, always keep Carbon Brushes [91] clean
and ensure that they slide freely within the brush
holders.
(6) Application of lubricant
Apply special grease (for hammer and rotary hammer) to the inner circumference of the Connecting Rod [34],
the O-rings [30] of the Striker [29] and the Piston [32], the sliding portion of the Second Hammer [19], the Oil
Seal [10], Oil Seal (A) [52], Oil Seal (B) [48], the Damper [21] and inner and outer circumferences of the
Bevel Gear [35]. Fill 50 g of the special grease in the Cylinder Crank Case [49] on the Connecting Rod [34]
side and 20 g in the Cylinder Crank Case [49] on the Clutch [31] side. Apply Hitachi Motor Grease No. 29 to
the Needle Bearing (M661) [65], the pinion portion of the Armature [82] and the Needle Roller D8 x 20 [16].
Fill 30 g of the Hitachi Motor Grease No. 29 in the Cylinder Crank Case [49] on the First Gear [64] side and
the Gear Cover [66] side.
Collar [51]
Ball Bearing
6002DDCMPS2L [53]
Bevel Pinion
Washer [54]
[50]
Spacer [60]
Fig. 23
--- 22 ---
Gear Holder [56]
Slot of gear
holder
Cross section A - A
7 mm
17 mm
Needle [58]
Spring (C) [57]
Feather Key
3 x 3 x 8 [44]
Wear limit
73
No. of carbon brush
("73" means the last
two digits of the code
number.)
Fig. 24