DeWalt D25900K User manual

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Full Strip down and Re-assembly procedure for the 10KG Demolition Hammer
D25900K.
This procedure is in Four main sections.
1. General Information / Tooling
2. Total Strip Down.
3. Re-assembly.
4. Routine Servicing.
Tool Holder
Anti-Vibration
Unit
Gearbox
Motor Unit
Crankcase
Piston &Cylinder
Beat Piece & Ram
Switch

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INDEX.
Page 3 General Information.
Page 4 Service Kits
Page 5 Hand Tools Required
Page 6-8 Service Tooling.
Dismantle
Page 9-10 Remove Tool Holder and Beat Piece.
Page 11-15 Tool Holder Assembly.
Page 16-17 Anti-Vibration Unit.
Page 18-25 Motor and Gearbox unit .
Re-assembly
Page 26-29 Gearbox and Crankshaft.
Page 30-33 Motor unit.
Page 34-36 Crankcase, Piston and Gear Case.
Page 36-39 Switch / Handle
Page 40-41 Cylinder and Ram.
Page 42-44 Anti-Vibration unit.
Page 45 SDS Spindle.
Page 46-47 Spindle & Flange
Page 48-50 Turning Sleeve.
Page 51-52 Tool Bit Locking assembly.
Page 53-57 Sliding Sleeve / Snap Ring.
Page 58-59 Beat Piece.
Page 60-61 Tool Holder SA to Product.
Routine Servicing
Page 62 Servicing.
Page 63 Fault Finding and Test Data.

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SECTION ONE.
General Information.
qONLY THE CORRECT GREASE MUST BE USED
qWhen repairing this product it is very important to keep the working area clean and free
from any dust or debris.
If any contamination is allowed within the Tool holder, Anti-vibration unit or Gear Box this
will cause premature failure of the Product.
qIf significant wear has occurred within in the Tool Holder components then it is
recommended to replace the complete unit (111).
qIf ANY of the O Rings are disturbed when dismantling, they must be replaced.
qIf only the Motor/Switch needs attention, it is not necessary to remove the Anti-Vibration &
Tool Holder units, although it can make the operation difficult if left attached, because of
the size and weight of the product.
If they are removed then the following should be noted
qOnly undo the 4 Screws (65) from the Anti-Vibration Unit and remove the complete front
assembly including the Tool Holder Unit from the Motor Housing.
qThe Piston, Crank Case, Cylinder & Anti-Vibration Unit will be exposed and should be
kept covered to prevent any ingress of dust or debris.
qThe O Ring’s (49) Piston and (79) Housing must be replaced on re-assembly.
Serial Number / Date Code.
A serial number and the Date code will be printed on the Main Metal Housing on the right
hand side next to the Anti-Vibration Unit. .
The Serial Number must be quoted on all repair documentation.
After repair, mark the housing next to the serial number with the letter ‘R’.

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Service Kits.
Four Service kits will be available that contain all the O Rings, Grease, Brushes, Snap Rings,
Seals that are required when Servicing.
The first service kit is used when the unit comes in for its first brush change after 250 hours.
The Major Kit is used when the unit requires a complete strip down and rebuild.
First Service Kit 115 Volt. First Service Kit 240Volt.
Item No Part number Qty. Item No Part Number Qty
8487340-01 2 8 487340-00 2
49 487213-00 1 49 487213-00 1
73 487297-00 1 73 487297-00 1
77 487296-00 1 77 487296-00 1
79 323711-44 1 79 323711-44 1
87 487238-00 1 87 487238-00 1
88 487205-00 1 88 487205-00 1
89 487241-00 1 89 487241-00 1
104 323711-40 1 104 323711-40 1
108 487243-00 1 108 487243-00 1
109 487299-00 1 109 487299-00 1
800 578970-02 1 800 578970-02 1
Major Service Kit 115 Volt.Major Service Kit 230 Volt.
Item No Part number Qty. Item No Part Number Qty
8487340-01 2 8 487340-01 2
32 487224-00 1 32 487224-00 1
36 487209-00 1 36 487209-00 1
49 487213-00 1 49 487213-00 1
52 323711-42 1 52 323711-42 1
58 324007-11 4 58 324007-11 4
69 487288-00 1 69 487288-00 1
71 487298-00 1 71 487298-00 1
73 487297-00 1 73 487297-00 1
74 323711-41 2 74 323711-41 2
77 487296-00 1 77 487296-00 1
79 323711-44 1 79 323711-44 1
87 487238-00 1 87 487238-00 1
88 487205-00 1 88 487205-00 1
89 487241-00 1 89 487241-00 1
90 487244-00 1 90 487244-00 1
104 323711-40 1 104 323711-40 1
108 487243-00 1 108 487243-00 1
109 487299-00 1 109 487299-00 1
800 578970-02 1 800 578970-02 1

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Hand Tools required.
Soft faced mallet.
T Handled Torx Screw Drivers. TX10. TX15. TX20.
Long Nose pliers.
Torque wrench. ½ in Drive.
Torque Screwdriver.
Allen Keys. Size various
Circlip Pliers. Internal, External.
Press.
Vice.
Two legged puller.

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Service tooling
559617-99 Crank Gear Removal & Assembly Tool.
Used to fit Double Gear ( 42 ) in conjunction with a Press.
Will remove and replace the crank gear ( 43 ) in conjunction with a Torque
Wrench
Used to fit Armature Seal (36) & Bearing (35) in conjunction with Service
Tool 559621-99.
559618-99 Motor assembly Tool.
Used to fit Motor Pot ( 2 ) & Armature ( 1 )

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559621-99 Armature Seal & Bearing assembly Tool.
Used to fit Seal (36) & Bearing (35)
559620-99 Spindle Seal & Tool Holder assembly Tool.
Used to fit Seal (108) & Spring Guide (98)

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559619-99 Snap Ring assembly Tool.
Used to remove and fit Snap Ring (88).

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SECTION TWO
Remove Tool Holder and Beat Piece.
qRemove Side handle (59) if fitted.
qUndo six screws (102) remove Tool Holder Assembly (111) a flat bladed
screwdriver may be required to Gently lever the housing away from the
Anti-vibration unit.
qBeware that the internal components will fall out from the Tool Holder
qRemove item (72) from inside the Housing.
qRemove the O Ring
qRemove items (67,68,69,70). From inside the Tool Holder Unit,

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qRemove Beat Piece Bearing item (110) from Spindle (107) (this may be tight),
qRemove O Ring (109).
qPull off Rubber Seal item (87). From end of Tool Holder Unit.