10 STRUCTURE AND FUNCTION ............................................. 10-1
20 TESTING AND ADJUSTING ................................................ 20-1
30 REMOVAL AND INSTALLATION ........................................... 30-1
40 MAINTENANCE STANDARD ............................................... 40-1
PC12R-8 PC15R-8
00-1
00-2
PC12R-8PC15R-8
The affected pages are indicated by the use of the
following marks. It is requested that necessary actions be taken to these pages according to table
below.
Proper service and repair is extremely important for the safe operation of your machine.
The service and repair techniques recommended by Komatsu Utility and describe in this manual are
both effective and safe methods of operation. Some of these operations require the use of tools specially
designed by Komatsu Utility for the purpose.
To prevent injury to workers, the symbols
ual. The cautions accompanying these symbols should always be carefully followed. If any danger arises
or may possibly arise, first consider safety, and take necessary steps to face.
andare used to mark safety precautions in this man-
SAFETY
GENERAL PRECAUTIONS
Mistakes in operation extremely dangerous.
Read all the Operation and Maintenance Manual carefully BEFORE operating the machine.
1. Before carrying out any greasing or repairs, read
all the precautions written on the decals which
are suck on the machine.
2. When carrying out any operation, always wear
safety shoes and helmet. Do not wear loose work
clothes, or clothes with buttons missing.
. Always wear safety glasses when hitting parts
with a hammer.
. Always wear safety glasses when grinding
parts with a grinder, etc.
3. If welding repairs are needed, always have a
trained, experienced welder carry out the work.
When carrying out welding work, always wear
welding gloves, apron, glasses, cap and other
clothes suited for welding work.
4. When carrying out any operation with two or more
workers, always agree on the operating procedure
before starting. Always inform your fellow workers
before starting any step of the operation. Before
starting work, hang UNDER REPAIR signs on
the controls in the operator's compartment.
5. Keep all tools in good condition and learn the correct way to use them.
6. Decide a place in the repair workshop to keep
tools and removed parts. Always keep the tools
and parts in their correct places. Always keep
the work area clean and make sure that there is
no dirt or oil on the floor.
Smoke only in the areas provided for smoking.
Never smoke while working.
PREPARATIONS FOR WORK
7. Before adding or making any repairs, park the machine on hard, level ground, and block the tracks
to prevent the machine from moving.
8. Before starting work, lower blade, bucket or any
other work equipment to the ground. If this is
not possible, use blocks to prevent the work
equipment from falling down. In addition, be sure
to lock all the control levers and hang warning
sign on them.
9. When disassembling or assembling, support the
machine with blocks, jacks or stands before starting work.
10. Remove all mud and oil from the steps or other
places used to get on and off the machine. Always
use the handrails, ladders or steps when getting
on or off the machine.
Never jump on or off the machine.
If it is impossible to use the handrails, ladders or
steps, use a stand to provide safe footing.
PRECAUTIONS DURING WORK
11. When removing the oil filler cap, drain plug or hydraulic pressure measuring plugs, loosen them
slowly to prevent the oil from spurting out.
Before disconnecting or removing components of
the hydraulic circuit and engine cooling circuit,
first remove the pressure completely from the circuit.
12. The water and oil in the circuits are not hot when
the engine in stopped, so be careful not to get
burned.
Wait for the oil water to cool before carrying out
any work on the cooling water circuits.
PC12R-8 PC15R-8
00-3
13. Before starting work, remove the leads from the
battery. Always remove the lead from the negative
( ± ) terminal first.
14. When raising heavy components, use a hoist or
crane. Check that the wire rope, chains and hooks
are free from damage.
Always use lifting equipment which has ample capacity. Install the lifting equipment at the correct
places.
Use a hoist or crane and operate slowly to prevent
the component from hitting any other part.
Do not work with any part still raised by the hoist
or crane.
15. When removing covers which are under internal
pressure or under pressure from a spring, always
leave two bolts in position on opposite sides.
Slowly release the pressure, then slowly loosen
the bolts to remove.
16. When removing components, be careful not to
break or damage the wiring.
Damage wiring may cause electrical fires.
17. When removing piping, stop the fuel or oil from
spilling out. If any fuel or oil drips on to the floor,
wipe it up immediately.
Fuel or oil on the floor can cause you to slip, or
can even start fires.
24. Take sure when removing or installing tracks.
When removing the track, the track separates
suddenly, so never let anyone stand at either
end of the track.
18. As a general rule, do not use gasoline to wash
parts. In particular, use only the minimum of gasoline when washing electrical parts.
19. Be sure to assemble all parts again in their original places. Replace any damage parts with new
parts.
When installing hoses and wires, be sure that
they will not be damaged by conctat with other
parts when the machine is being operated.
20. When installing high pressure hoses, make sure
that they are not twisted. Damaged tubes are dangerous, so be extremely careful when installing
tubes for high pressure circuits. Also, check that
connecting parts are correctly tightened.
21. When assembling or installing parts, always use
specified tightening torques.
When installing the parts which vibrate violently or
rotate at high speed, be particulary careful to
check that they are correctly installed.
22. When aligning two holes, never insert your fingers
or hand.
23. When measuring hydraulic pressure, check that
the measuring tool is correctly assembled before
taking any measurement.
00-4
PC12R-8 PC15R-8
FOREWORD
This shop manual has been prepared as an aid to improve the quality of repairs by giving the operator an accurate understanding of the product and by showing him the correct way to perform repairs and make judgements.
Make sure you understand the contents of this manual and use it to full effect at every opportunity.
This shop manual mainly contains the necessary technical information for operations performed in a service
workshop.
The manual is divided into chapters on each main group of components; these chapters are further divided into
the following sections.
STRUCTURE AND FUNCTION
This section explains the structure and function of each component. It serves not only to give an understanding of the structure, but also serves as reference material for troubleshooting.
TESTING AND ADJUSTING
This sections explains checks to be made before and after performing repairs, as well as adjustments to be
made at completion of the checks and repairs.
Troubleshooting charts correlating «Problems» to «Causes» are also included in this section.
DISASSEMBLY AND ASSEMBLY
This section explains the order to be followed when removing, installing, disassembling or assembling
each component, as well as precautions to be taken for these operations.
MAINTENANCE STANDARD
This section gives the judgement standards when inspecting disassembled parts.
NOTICE
The specifications contained in this shop manual are subject to change at any time and without any
notice.
Contact your Komatsu Utility distributor for the latest information.
PC12R-8 PC15R-8
00-5
HOW TO READ THE SHOP MANUAL
HOW TO READ THE SHOP MANUAL
VOLUMES
Shop manual are issued as a guide to carry out repairs. These various volumes are designed to avoid
duplicating the same information.
DISTRIBUTION AND UPDATING
Any additions, amendments or other changes will
be sent to Komatsu Utility distributors.
Get the most up-to-date information before you start
any work.
FILING METHOD
1. See the page number on the bottom of the page.
File the pages in correct order.
2. Following examples show you how to read the
page number.
Example
10 - 3
Item number (10. Structure
and function)
Consecutive page number for
each item
3. Additional pages: additional pages are indicated
by a hyphen (-) and number after the page number.
Fle as in the example.
Example:
10-4
10-4-1
10-4-2
] Added pages
10-5
SYMBOLS
In order to make the shop manual greatly chelpful,
important points about safety and quality are marked
with the following symbols.
SymbolItemRemarks
Special safety precautions are necessary when performing the
work.
Safety
Caution
Weight
Tightening
torque
Coat
Oil, water
Drain
Extra special safety precautions
are necessary when performing
the work because it is under internal pressure.
Special technical precautions or
other precautions for preserving
standards are necessary when
performing the work.
Weight of parts or systems.
Caution necessary when selecting
hoisting wire, or when working
posture is important, etc.
Parts that require special attention
for the tightening torque during assembly.
Parts to be coated with adhesives
and lubricants etc.
Places where oil, water or fuel
must be added, and their quantity.
Places where oil or water must be
drained, and quantity to be
drained.
REVISED EDITION MARK
(123....)
When a manual is revised, an edition mark is re-
corded on the bottom outside corner of the pages.
REVISIONS
Revised pages are shown on the LIST OF REVISED PAGES between the title page and SAFETY
page.
00-6
PC12R-8 PC15R-8
HOISTING INSTRUCTIONS
HOISTING INSTRUCTIONS
Heavy parts (25 kg or more) must be lifted
with a hoist etc. In the Disassembly and As-sembly section, every part weighing 25 kg or
more is clearly indicated with the symbol
1. If a part cannot be smoothly removed from the
machine by hoisting, the following checks should
be made:
. Check for removal of all bolts fastening the part
to the relative parts.
. Check for any part causing interference with
the part to be removed.
2. Wire ropes
1) Use adequate ropes depending on the weight
of parts to be hoisted, referring to the table below:
WIRE ROPES
(Standard «S» or «Z» twist ropes
without galvanizing)
Rope diameter (mm)Allowable load (tons)
10
11.2
12.5
14
16
18
20
22.4
1.0
1.4
1.6
2.2
2.8
3.6
4.4
5.6
ing, and a serious accident can result.
Hooks have maximum strength at the middle
portion.
3) Do not sling a heavy load with one rope alone,
but sling with two or more ropes symmetrically
wound on to the load.
Slinging with one rope may cause turning of
the load during hoisting, untwisting of the
rope, or slipping of the rope from its original
winding position on the load, which can
cause dangerous accidents.
4) Do not sling a heavy load with ropes forming a
wide hanging angle from the hook.
When hoisting a load with two or more ropes,
the force subjected to each rope will increase
with the hanging angles.
The table below shows the variation of allowable load (kg) when hoisting is made with two
ropes, each of which is allowed to sling up to
1000 kg vertically, at various handing angles.
When two ropes sling a load vertically, up to
2000 kg of total weight can be suspended.
This weight becomes 1000 kg when two ropes
make a 120ë hanging angle.
On the other hand, two ropes are subjected to
an excessive force as large as 4000 kg if they
sling a 2000 kg load at a lifting angle of 150ë.
30
40
50
60
The allowable load value is estimated to be
one-sixth or one-seventh of the breaking
strength of the rope used.
2) Sling wire ropes from the middle portion of the
hook. Slinging near the edge of the hook may
cause the rope to slip off the hook during hoist-
10.0
18.0
28.0
40.0
PC12R-8 PC15R-8
00-7
STANDARD TIGHTENING TORQUE
STANDARD TIGHTENING TORQUE
The following charts give the standard tightening torques of bolts and nuts. Exceptions are given in sections of «Disassembly and Assembly».
1. STANDARD TIGHTENING TORQUE OF BOLTS AND NUT
Width across flat
Thread diameter
of bolts
(mm)
Pitch of
bolts
(mm)
(mm)
kgmNmkgmNm
10
12
14
16
18
20
22
24
27
30
33
36
6
8
1
1.25
1.5
1.75
2
2
2.5
2.5
2.5
3
3
3.5
3.5
4
10
13
17
19
22
24
27
30
32
36
41
46
50
55
5
6
8
10
12
14
14
17
17
19
19
22
24
27
0.96w0.1
2.3w0.2
4.6w0.5
7.8w0.8
12.5w1
19.5w2
27w3
38w4
52w6
66w7
96w10
131w14
177w20
230w25
9.5w1
23w2
45w4.9
77w8
122w13
191w21
262w28
372w40
511w57
644w70
945w100
1287w140
1740w200
2250w250
1.3w0.15
3.2w0.3
6.5w0.6
11w1
17.5w2
27w3
37w4
53w6
73w8
92w10
135w15
184w20
250w27
320w35
13.5w1.5
32.2w3.5
63w6.5
108w11
172w18
268w29
366w36
524w57
719w80
905w98
1329w140
1810w190
2455w270
3150w350
39
This torque table does not apply to bolts or nuts which have to fasten nylon or other parts non-ferrous metal washer.
. Nm (Newton meter): 1 Nm = 0.102 kgm
4
60
Ð
295w33
2900w330
410w45
00-8
4050w450
PC12R-8 PC15R-8
STANDARD TIGHTENING TORQUE
2. TIGHTENING TORQUE FOR NUTS OF FLARED
Use these torques for nut part of flared.
Thread diameter
of nut part
(mm)
1/2" - 20
9/16" - 18
3/4" - 16
7/8" - 14
1
1.
/16"-12
5
/16"-12
1.
5/8"
1.
-12
22
33
Width across flats
of nut part
(mm)
17
17
22
27
32
38
50
27
41
TIGHTENING TORQUE
kgmNm
2.6w0.5
4w0.5
6.7w2
8w2
9.7w3
17w3
20w5
8w2
20w5
25.5w4.9
39.2w4.9
65.7w19.6
78.5w19.6
95.15w29.4
166.7w29.4
196.2w49
78.5w19.6
196.2w49
COATING MATERIALS
The recommended coating materials prescribed in Komatsu Utility Shop Manuals are listed below:
NomenclatureCodeApplications
Used for low resistance locking of screws, check nuts and adjustment nuts.
To prevent the loosening of bolts, nuts and plugs and the leakage of oil. Used for
medium resistance locking of screws and nuts of every type, and for locking keys
and bearings.
Used for high resistant of threaded parts that can be removed with normal tools.
Used for high resistant locking and for sealing threaded parts, bolts and stud
bolts.
Used for sealing the union threads for hydraulic tubes.
Used for sealing rather exact plane surfaces when the option of possible future
dismantling is required.
Used for high resistant locking of mechanical components that can be removed
only after heating
Used to lock cylindrical couplings and for the permanent locking of threaded parts,
and also to lock shafts to bearings, gears, pulleys, pins, bushings, etc.
Used by itself on mounting surface on the final drive and transmission cases.
(Clearance between flange surfaces within 0.2 mm).
Used by itself on mounting flat surface
(Clearance between surfaces within 0.5 mm)
Applied to bearings, sliding parts and oil seals for lubrication, rust prevention and
facilitation of assembling work.
Used for protecting battery electrode terminals from corrosion.
Adhesives
Gasket sealant
Grease
(Lithium grease)
Vaseline
Loctite 222
Loctite 242
Loctite 262
Loctite 270
Loctite 542
Loctite 573
Loctite 601
Loctite 675
Loctite 510
Loctite 518
ASL800050
±
PC12R-8 PC15R-8
00-9
ELECTRIC WIRE CODE
CABLE
ELECTRIC WIRE CODE
In the wiring diagrams various colours and symbols are employed to indicate the thickness of wires.
This wire code table will help you understand WIRING DIAGRAMS.
Example: R -N 1.5 indicates a cable having a nominal number 1.5 and red coating with black stripe.
CLASSIFICATION BY THICKNESS
Nominal
number
0.8110300.782.808Instruments, sensor
1140.300.992.8011Warning light, light etc.
1.5210.301.483.3514Working beam, solenoid valve, etc.
2.5350.302.473.8020Control panel, etc.
4560.303.954.6028Pre-heating
6840.305.935.2037Control panel
251890.423.759.3100Ground - Starter motor
Number
strands
Copper wire
ù of strands
(mm)
Cross section
(mm
2
)
Cable O.D.
(mm)
Current rating
(A)
Applicable circuit
CLASSIFICATION BY COLOUR AND CODE
PrimaryAuxiliary
CodeAA ±RA/RA ± GA/GA ±BA/BA ±NA/N
ColourLight blueLight blue - RedLight blue - YellowLight blue - WhiteLight blue - Black
ColourRedRed - OrangeRed - GreenRed - BlackRed - White
CodeSS ±NS/NÐРРРРР
ColourPinkPink - BlackÐÐÐ
CodeVV ±NV/NÐРРРРР
ColourGreenGreen - BlackÐÐÐ
CodeZZ ± GZ/GÐРРРРР
ColourVioletViolet - YellowÐÐÐ
COMPOSITION OF THE COLOURS
The coloration of two-colour wires is indicated by the composition of the symbols listed.
Example: G-V = Yellow-Green with longitudinal colouring.
G/V = Yellow-Green with transversal colouring.
00-10
PC12R-8 PC15R-8
WEIGHT TABLE
This weight table is a guide for use when transporting or handling components.
Unit: kg
Machine modelPC12R-8PC15R-8
From serial no.F31605-F22426-
Engine assembly (dry)
. Engine
. Engine support
. Power train
. Pump
Radiator - exchanger66
Revolving frame620620
Cabin180180
Canopy7070
Seat support3737
Seat1717
Platform55
Engine hood44
Fuel tank (without fuel)2.52.5
Hydraulic tank (without hydraulic oil)1616
Control valve3232
Rear counterweight4848
Lateral counterweight23+2323+23
Swing motor2727
Swivel joint5.55.5
Track frame assembly770 (720)770 (720)
Track roller3x63x6
Idler assy.1717
Final drive1717
Sprocket55
Swing circle2020
Track shoe
. Steel track shoe L=230 mm
. Rubber track shoe
Swing bracket2222
Boom4851
Arm
. Standard
. Long arm
Bucket (standard)2122
Blade4354
Boom cylinder10.712
Arm cylinder1011
Bucket cylinder99
Boom swing cylinder1010
Blade cylinder6.811
100
77
7
8
5.3
70x2
45x2
23
36
112
77
7
8
19
70x2
45x2
25
38
(): For rubber track shoe
PC12R-8 PC15R-8
00-11
TABLE OF OIL AND COOLANT QUANTITIES
RESERVOIR
Crankcase sump2.82.8
Hydraulic circuit2422
Final drive
(each)
KIND OF
FLUID
AMBIENT TEMPERATURECAPACITY (
±20±100102030ëC
SAE 10W
SAE 20W-20
SAE 30
SAE 40
SAE 10W
SAE 10W
SpecifiedRefill
0.40.4
< )
]
Fuel tank
Engine coolant
system
FUEL20Ð
WATER+
ANTI-FREEZE
WATER3.2Ð
PERMANENT
LIQUID
ASTM D975 N. 2
3.2Ð
3.2Ð
] ASTM D975 N. 1
ASTM: America Society of Testing and Materials
SAE: Society of Automotive Engineers
API: American Petroleum Institute
MIL: USA Military Specification
CCMC: Common Market Constructors Committe
Specified capacity: Total amount of oil including oil for components and oil in piping.
Refill capacity: Amount of oil needed to refill system during normal inspection and maintenance.
NOTE:
(1) When fuel sulphur content is less than 0.5%,
change oil in the oil pan ebery periodic maintenance hours described in operation and maintenance manual.
Change oil according to the following table if fuel
sulphur content is above 0.5%.
Fuel sulphur content
0.5 to 1.0%1/2 of regular interval
Above 1.0%1/4 of regular interval
Oil change interval in engine oil
pan
(3) Use classification CD as engine oil, if use classifi-
cation CC, reduce the engine oil change interval to
half.
(4) Use original products, which have characteristics
specifically formulated and approved for the engine, the hydraulic circuit of equipment and for reductions.
(2) When starting the engine is weathers temperature
below 0ëC, be sure to use engine oil SAE 10W,
SAE 20W-20, even if weather temperature goes
up to 10ëC day time.