O Ring 22 - Makita HR4001C Technical Information

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epair
[3] DISASSEMBLY/ASSEMBLY
7) Place Piston at the rear dead point by turning Crank shaft. Then remove Piston and Rod from Crank shaft.
O ring 21 and O ring 22 can now be replaced. (Fig. 22)
Fig. 22
Place Piston at the rear dead point
by turning Crank shaft.
ASSEMBLING
Do the reverse of the disassembling steps.
Note:
1) When assembling Cylinder 28.5 to Crank housing complete;
Do not forget to install two diameter 30 O rings and Ring spring 32
as illustrated in Fig. 23.
Use arbor press to insert the Cylinder into Crank housing complete
if No.1R213 and No.1R350 are not available.
2) Do not forget to put Ring 33 on Cylinder 28.5 when locking the
Cylinder to Crank housing complete with Ring spring 31. (Fig. 18)
[3] -4. Motor and Gear Section
DISASSEMBLING
1) From Crank housing complete, remove Crank housing cover (Fig. 6) and Handle (Fig. 14).
It is not necessary to remove Change lever and Crank cap cover in this step.
2) After removing Rear cover, disconnect the connector of Lead unit from Controller. Then remove each two 4x14
Tapping screws that fasten Controller and Cord clamp base to Motor housing. Cord clamp base can now be removed.
(Fig. 24)
3) Remove Controller from Motor housing by levering up with screwdriver. Then move the spiral spring of Brush holder
unit off Carbon brush, and pull out Carbon brush to disconnect from Armature's commutator. (Fig. 25)
Fig. 24
Rear cover
Tapping screw
4x18
Piston
Connector of
lead unit
Tapping screw
4x14
Cord clamp base
Connecting rod

O ring 22

Fig. 23
Cylinder 28.5
Fig. 25
Spiral spring
of brush holder unit
P 9 /20
Pin 7
Piston Connecting rod
O ring 21
Ring spring 32
O ring 30
Carbon brush
Controller