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SEN04306-04 HYDRAULIC PC18MR EXCAVATOR 20001 SERIAL NUMBERS and up...
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SEN04308-04 HYDRAULIC EXCAVATOR PC18MR-3 Machine model Serial number PC18MR-3 20001 and up 00 Index and foreword 100 Index Composition of shop manual .......................... 2 Table of contents ............................. 4 PC18MR-3 00-100 Find manuals at https://best-manuals.com...
300 Troubleshooting of hydraulic and mechanical system (H-mode) ........SEN04499-00 400 Troubleshooting of engine (S-mode).................. SEN04500-00 50 Disassembly and assembly......................SEN04325-00 100 General information on disassembly and assembly ............SEN04620-00 200 Engine and cooling system ....................SEN04621-00 300 Power train......................... SEN04622-00 00-100 PC18MR-3 Find manuals at https://best-manuals.com...
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400 Undercarriage and frame ....................SEN04623-00 500 Hydraulic system ........................SEN04624-00 600 Work equipment .........................SEN04625-00 700 Cab and its attachments.....................SEN04626-00 800 Electrical system ........................SEN04627-00 90 Diagrams and drawings ......................SEN04326-01 100 Hydraulic diagrams and drawings ..................SEN04327-00 200 Electrical diagrams and drawings..................SEN04328-01 PC18MR-3 00-100 Find manuals at https://best-manuals.com...
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Center swivel joint ............................Travel motor ..............................Hydraulic cylinder............................14 Solenoid valve............................... 18 Variable gauge valve............................. 21 Multi-control valve (If equipped) ........................22 420 Hydraulic system, Part 2 SEN04317-00 Hydraulic pump ............................. Control valve ..............................00-100 PC18MR-3 Find manuals at https://best-manuals.com...
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Inspection procedures for diode ........................39 How to start operation of KOMTRAX terminal ....................40 Lamp display of KOMTRAX terminal......................44 Removal and installation of KOMTRAX terminal ................... 47 Preparation work for troubleshooting of electrical system ................48 PC18MR-3 00-100 Find manuals at https://best-manuals.com...
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H-25 Hydraulic drift of swing is large......................25 H-26 Speed or power of blade is low ......................26 H-27 Blade does not move..........................27 H-28 Hydraulic drift of blade is large ......................27 H-29 Variable gauge does not move......................28 00-100 PC18MR-3 Find manuals at https://best-manuals.com...
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Removal and installation of KOMTRAX terminal ................... 90 Diagrams and drawings 100 Hydraulic diagrams and drawings SEN04327-00 Hydraulic circuit diagram ..........................200 Electrical diagrams and drawings SEN04328-01 Electrical circuit diagram..........................Connector list and stereogram ........................PC18MR-3 00-100 Find manuals at https://best-manuals.com...
SEN04309-00 HYDRAULIC EXCAVATOR PC18MR-3 Machine model Serial number PC18MR-3 20001 and up 00 Index and foreword 200 Foreword and general information Safety notice ..............................2 How to read the shop manual ......................... 7 Explanation of terms for maintenance standard ..................... 9 Handling of electric equipment and hydraulic component ................11...
Proper service and repair are extremely important for safe machine operation. The service and repair techniques recommended by Komatsu and described in this manual are both effective and safe. Some of these techniques require the use of tools specially designed by Komatsu for the specific purpose.
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Operate the hoist or crane slowly to prevent the component from hitting any other part. Do not work with any part still raised by the hoist or crane. PC18MR-3 00-200...
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If you grasp them, your fingers as large as 39.2 kN {4,000 kg}. may be caught. After the wire ropes are stretched, stop the crane and check the condi- tion of the slung load, wire ropes, and pads. 00-200 PC18MR-3...
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11) After operating the hoist, do not swing the control switch. 12) Remember the position of the main switch so that you can turn off the power immedi- ately in an emergency. PC18MR-3 00-200...
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When connecting the refrigerant pip- ing, apply compressor oil for refriger- ant (R134a) (DENSO: ND-OIL8, VA L E O T H E R M A L S Y S T E M S : ZXL100PG (equivalent to PAG46)) to its O-rings. 00-200 PC18MR-3...
Engine volume This section explains the method of reproducing, repairing, and replacing parts. Revision and distribution Any additions, revisions, or other change of notices will be sent to KOMATSU distributors. Get the most up-to-date information before you start any work. PC18MR-3...
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Places where oil, etc. must be drained, and quantity to be drained. Units In this shop manual, the units are indicated with International System of units (SI). For reference, con- ventionally used Gravitational System of units is indicated in parentheses { }. 00-200 PC18MR-3...
The tightness of fit is decided by the toler- ance. Indication of size of rotating shaft and hole and relationship drawing of them Example: Tolerance Standard size Shaft Hole –0.030 +0.046 –0.076 PC18MR-3 00-200...
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If a product is worn to the allowable value, it must be checked or repaired. Since the permissible value is estimated from vari- ous tests or experiences in most cases, however, it must be judged after consider- ing the operating condition and customer's requirement. 00-200 PC18MR-3...
The pins of the male and female connec- tors are in contact at the crimped terminal or soldered portion, but if there is exces- sive force brought to bear on the wiring, the plating at the joint will peel and cause improper connection or breakage. PC18MR-3 00-200...
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If there is oil or water in the com- pressed air, the contacts will become even dirtier, so remove the oil and water from the compressed air com- pletely before cleaning with com- pressed air. 00-200 PC18MR-3...
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If the machine is left disassem- bled for a long time, it is particu- larly easy for improper contact to occur, so always cover the con- nector. PC18MR-3 00-200...
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If the connector cannot be cor- rected easily, remove the clamp and adjust the position. If the connector clamp has been removed, be sure to return it to its original position. Check also that there are no loose clamps. 00-200 PC18MR-3...
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(2) while moving it up and down until the locks are set normally. Arrow: 1), 2), 3) a Right of figure: Lock (a) is pulled down (not set completely) and lock (b) is set completely. (1): Male connector (2): Female connector (a), (b): Locks PC18MR-3 00-200...
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After completely drying the con- n e c t o r, b l o w i t w i t h c o n ta c t restorer and reassemble. 00-200 PC18MR-3...
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If there is any change, there is proba- bly defective contact in that circuit. PC18MR-3 00-200...
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If an oil clean- ing device is used, it is possible to filter out the dirt that has collected during storage, so this is an even more effective method. 00-200 PC18MR-3...
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The oil cleaning equipment is used to remove the ultra fine (about 3 ) particles that the filter built in the hydraulic equipment can- not remove, so it is an extremely effective device. PC18MR-3 00-200...
Even if lock (L2) is pressed, connec- tor (1) cannot be pulled out toward you, if part A does not float. In this case, float part A with a small screw- driver while press lock (L2), and then pull out connector (1) toward you. 00-200 PC18MR-3...
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If the lock is on the underside, use flat-head screwdriver [1] since you cannot insert your fingers. While pressing up lock (C) of the connec- tor with flat-head screwdriver [1], pull out connector (3) in the direction of the arrow. PC18MR-3 00-200...
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Insert the connector to the end, while setting its groove. Turn housing (H1) in the direction of the arrow until it “clicks”. Example) Speed sensor of fuel supply pump: G (SUMITOMO-3) a Pull the connector straight up. 00-200 PC18MR-3...
(Nominal No. 3 and below) Insulator Soft polyvinyl chloride automobile Conduc- Annealed copper for elec- Heat-resis- General wiring in extremely tric appliance tant low-volt- –50 to +110 cold district, wiring at high-tem- age wire for Heat-resistant crosslinked perature place Insulator automobile polyethylene PC18MR-3 00-200...
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(approx.) 10.4 12.0 13.6 Standard – – – – – – – – – Cov- Standard 10.8 11.4 13.0 13.6 16.0 17.6 er D Standard 10.8 11.4 13.0 13.6 16.0 17.6 “f” of nominal No. denotes flexible”. 00-200 PC18MR-3...
07371-30400 07379-00500 07378-10500 07371-30500 If the part is not under hydraulic pressure, the following corks can be used. Dimensions Nominal Part Number number 07049-00608 07049-00811 07049-01012 07049-01215 07049-01418 11.5 07049-01620 13.5 07049-01822 07049-02025 07049-02228 18.5 07049-02430 07049-02734 22.5 00-200 PC18MR-3...
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If any part is loosened or damaged, retighten or repair it. Fuel system Check the piping for damage, the mounting bolts and nuts for looseness, and the joints for fuel leakage. If any part is loosened or damaged, retighten or repair it. PC18MR-3 00-200...
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If any bolt or nut is loosened, retighten it. Checking muffler function Check the muffler for abnormal sound and sound different from that of a new muffler. If any abnormal sound is heard, repair the muffler, referring to “Troubleshooting” and “Disassembly and assembly”. 00-200 PC18MR-3...
After inserting the hose in the mating adapter perfectly, pull it back to check its connecting condition. (Fig. 5) a When the hose is pulled back, the rubber cap portion moves toward the hose about 3.5 mm. This does not indicate abnormality, however. PC18MR-3 00-200...
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2), pull out whole body (7) to discon- nect it. (Fig. 8) Connection Hold the tightening portion and push body (7) straight until sliding prevention ring (6) contacts contact surface (a) of the hexag- onal portion at the male end. (Fig. 9) 00-200 PC18MR-3...
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2), pull out whole body (9) to discon- nect it. (Fig. 12) Connection Hold the tightening portion and push body (9) straight until the sliding prevention ring contacts contact surface (b) of the hexag- onal portion at the male end. (Fig. 13) PC18MR-3 00-200...