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Yuchai U27 Instruction Manual

Hydraulic excavator
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U27 Hydraulic
Excavator
Instruction
Manual
Guangxi Yuchai Heavy Industry Co., Ltd.

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Summary of Contents for Yuchai U27

  • Page 1 U27 Hydraulic Excavator Instruction Manual Guangxi Yuchai Heavy Industry Co., Ltd.
  • Page 2 ⚫ Before officially operating this machine at the worksite, you should have been trained on the safe operation of the machine in advance. You are responsible for complying with relevant laws and regulations and complying with Yuchai Heavy Industry's instructions on machine operation and maintenance.

  • Page 3: Table Of Contents

    Contents 1. PREFACE ................... 1-2 O USERS ................ 1-3 RODUCT NFORMATION ................1-5 ACHINE DIRECTION ................ 1-6 ACHINE COMPONENTS ................1-7 ACHINE OVERVIEW ..............1-8 AFETY RELATED NFORMATION ..............1-9 ECHNICAL SPECIFICATIONS 2. SAFETY REGULATIONS ..............2-2 AFETY GENERAL PRINCIPLES .................
  • Page 4 ..............4-16 ONSTRUCTION WORK GUIDE ............4-19 EMOVAL AND INSTALLATION OF BUCKET ................4-20 ARK THE MACHINE ................4-22 FTER OPERATION .......... 4-23 OADING UNLOADING AND TRANSPORTATION OF MACHINES ............... 4-28 ORKING IN COLD HOT CLIMATES ..............4-29 TORAGE OF THE MACHINE ..........

  • Page 5: Preface

    Preface...

  • Page 6: To Users

    Please hand over this manual together when transferring this machine, so that the next owner can use it correctly. Please entrust the agent or maintenance station of Yuchai Heavy Industry to overhaul and adjust the machine, and use the original accessories and spare parts provided by our company. If you use the non-original accessories or components, there may be no obvious impact on the machine for the time being, but it is likely to cause a series of undesirable results to the machine in the future.

  • Page 7: Product Information

    Machine information (the nameplate of the machine is on the front left side of the ⚫ platform) Hydraulic excavator Rated Model: YG power: Machine Factory weight: number: Executive standard: Q/YCG 2038 Guangxi Yuchai Heavy Industry Co., Ltd. Yuchai Construction Machinery Intensive Industrial Park of Luchuan, Yulin, Guangxi Engine information ⚫ (Serial (Model) number)
  • Page 8 Fill the machine number and engine serial number of your machine in the below table. When you need to purchase machine parts or want to obtain relevant information, you can inform Yuchai Heavy Industry of these codes. Please record these numbers and keep them together with the product certificate. If your machine has been stolen accidentally, you can submit the information to the local public security agency.

  • Page 9: Machine Direction

    Machine direction The front, back, left, right, up and down in this manual refer to the directions shown in the figure. Down Right Front Rear Left...

  • Page 10: Machine Components

    Machine components 1. Bucket cylinder 12. Track 2. Bucket 13. Walking reducer 3. Stick 14. Drive wheel 4. Stick cylinder 15. Thrust wheel 5. Boom 16. Supporting wheel 6. Boom cylinder 17. Rotary support 7. Cab shed 18. Frame 8. Instrument 19.

  • Page 11: Machine Overview

    Machine overview Assigned operation This machine is mainly used for the following operations: ● Excavation operation ● Trenching operation ● Loading operation ● Leveling operation Please refer to the contents of operation guide and annex guide for detailed operation essentials. Run-in The machine has been fully adjusted and checked before delivery.

  • Page 12: Safety Related Information

    Safety related Information Most accidents related to operation, inspection, maintenance and repair operations are caused by negligence of basic precautions and hazard prediction in safety. The accidents can be prevented by predicting possible dangerous situations. Therefore, attention must be paid to the location and type of hazards. (In order to carry out such operations correctly, the operator must have the specified training, technology and tools.) Please carefully read this manual and all safety precautions, warnings and accident prevention methods recorded on the machine, and understand their contents until you fully understand them.

  • Page 13: Technical Specifications

    Technical specifications 1. Structural dimension parameters Code Item Unit U27-AF51 Working weight 2600 (rubber track, four-post shed) Standard bucket capacity 0.09 Yanmar 3TNV76-P (China III/Euro V) or Yanmar 3TNV80F (China Engine model IV/Euro V/T4) Engine power KW/rpm 14.5/2400 or 15.2/2500 (2200 rpm set by the manufacturer)
  • Page 14 2. Working parameters Code Item Unit U27-AF51 Maximum digging height 4170 Maximum unloading height 2780 Maximum digging depth 2540 Maximum vertical digging depth 2240 Minimum turning radius of the working device 1950 Maximum ground digging radius 4400 Maximum digging radius...
  • Page 15 3. Walking mechanism Independently driven by a hydraulic motor through a multi-stage planetary gearbox. Walking speed (km/h) Gradeability High speed 58%(30°) Low speed Hydraulic system Load sensitive system Maximum system flow: 61.6 L/min (at 2200 rpm) System rated pressure: 24 MPa Rotary pressure: 17.5 MPa Auxiliary 1/Auxiliary 2 pressure: 21 MPa Pilot pressure: 3.5 MPa...
  • Page 16 7. Interference on machine body The working devices of various series of hydraulic excavators may interfere with the boom oil cylinder or the boom lower cover plate when they are non-standard working devices. Therefore, the attention should be paid to the angle between the stick and the boom when retracting the stick if the machine uses non-standard working devices to prevent interference with the boom oil cylinder and damage to the machine body.

  • Page 17: Safety Regulations

    Safety regulations...

  • Page 18: Safety General Principles

    Safety general principles Following the relevant safety regulations in this manual can avoid most accidents that endanger the operation and maintenance of the machine. Before you operate or overhaul the machine, you should read and understand all the safety information in this manual and the safety diagrams of the machine. The safety-related content in this manual points out the situations that may occur during the normal operation and maintenance of the machine, and gives possible solutions to these situations.

  • Page 19: Safety Tips

    Safety tips 1. Warning signs In this manual, this warning sign points out important information about safety. When you see this sign, you should carefully read the information and advice behind the sign to avoid possible casualties. 2. Safety reminders This instruction provides precautions, signs and descriptions of potential hazards for the safe use of the machine.

  • Page 20: Safety Equipment

    Safety equipment 1. Protective equipment for operators 1) The operator must wear tight-fitting and suitable work clothes, safety helmets, working leather shoes and other related safety protection equipment (such as: protective earplugs, gloves, protective glasses, seat belts, etc.) before operation or maintenance. 2) If the operator's hair is too long, please tie it up and cover it with a safety cap to prevent it from being entangled by the machine.

  • Page 21: Safety Signs

    Safety signs Warning: Failure to understand the safety signs or loss of safety signs may result in injury or death. Please replace the missing or damaged signs in time, and keep the surfaces of all safety signs clean and easy to distinguish. Before operating, maintaining and repairing the machine, you must carefully read the instruction manual and the warning signs affixed to the machine to ensure that you fully understand its contents and follow the relevant procedures.
  • Page 22 2. Safety sign pasting location The sign shown in the graphics is only the "safety sign" part of all signs, and the rest of the function signs will be introduced in the following chapters.
  • Page 23 3. Safety labels and other signs 1) Pay attention to and stay away from the working 4) Warning sign devices Movement of the working devices can cause personal 5) Warning sign injury. A safe distance must be kept from the working area of the working device.
  • Page 24 7) Lifting combination sign 10) Read the instructions sign 8) Warning sign 11) Lubrication sign Caution 1. The points shown in the figure are lubricating oil injection points. It is required to check whether the mechanism lubricated 9) Warning sign at the injection points is lubricated normally every day;...
  • Page 25 13) Safety sign 16) Throttle sign 17) Bulldozing operation 14) Tail trademark 15) Warning sign 18) Manipulation sign...
  • Page 26 19) Lifting sign of whole machine 22) Motor warning sign 20) Please keep safe when getting on or off the 23) Fire sign machine When getting on and off the car, move slowly, grab the 24) Maintenance warning board handrails on both sides, face the machine, and use the steps and track shoes on the machine.

  • Page 27: Safety In The Workplace

    Safety in the workplace Know the area where you will work as much as possible in advance. Please check: 1. The location of the slope. 2. Open ditch. 3. Falling objects or hanging objects. 3. Soil condition (soft or hard). 4.

  • Page 28: Safe Operation

    Safe operation Warning: it is strictly forbidden to carry or lift people with excavators. Warning: before operating the machine, you must wear a seat belt, honking the horn, and confirm that there is no one around the working area before starting work. 1.
  • Page 29 2. Walking and turning 1) Please turn the upper part of the machine platform to a Working device proper position before walking. The working device and the bulldozer shovel are in the same direction. If the working device and the bulldozer shovel are in the opposite direction, the operation is reversed.
  • Page 30 4) When the machine is walking or in operation, be sure to keep a safe distance from people, buildings or other machines to avoid contact with them. 5) When walking through underground passages, under bridges, or under power lines and other places with limited heights, be sure to have gesture commands.
  • Page 31 5) Do not make a turn on the slope or cross the slope. Be sure to go down to a flat place to change the position of the machine, and then go up the slope. 6) When working on a slope, you must start from a high place and gradually dig down the slope, with the bulldozing board at the back and pressing the ground, and the unloading position should be in the uphill direction.
  • Page 32 10) It is strictly forbidden to drive or work on a slope with a longitudinal gradient greater than 25 degrees. 11) It is strictly forbidden to drive or work on slopes with a lateral gradient greater than 15 degrees. 12) Keep the balance of the machine as much as possible, and it is strictly forbidden to walk on rocks or cross obstacles.
  • Page 33 16) When working on a slope, the machine may lose its balance and tip over when operating the swing or the working device. This can cause serious injury or equipment damage. Therefore, when performing these operations, use soil to build a strong platform that can keep the machine level.
  • Page 34 6) When the bucket is subjected to special resistance on the ground, do not walk or rotate, otherwise, the machine will be damaged. 7) During operation, if the hydraulic cylinder is operated to Margin the end of the stroke, the force will act on the limit ring inside the cylinder, thereby reducing the service life of the machine.
  • Page 35 13) Do not excavate when the track is off the ground, otherwise, the machine and structure will be damaged. 14) Do not use the weight of the machine to increase the digging force of the machine. 15) Do not use the falling force of the bucket as a pick, breaker or pile driver, as this will cause excessive force on the rear of the machine.
  • Page 36 17) Do not use the falling force of the machine to excavate, otherwise, the machine will be damaged. 18)Do not use turning force to compact the soil or damage mounds and walls. When turning, do not insert the bucket teeth into the soil, as these actions will damage the working device.
  • Page 37 20) Do not dig the working surface under the suspended part, otherwise, there will be the danger of falling rocks or the suspended part collapsing and hitting the machine. 5. Anti-dumping, anti-skidding and disposal during operation Warning: 1) When you have to turn on a ramp, you can only turn in a large arc. When the machine is about to turn to the right, extend the boom and stick to the left, the bucket is about 30 cm away from the ground, and lock the platform.

  • Page 38: Machine Transportation And Handling

    Machine transportation and handling The transportation (loading and unloading) of excavators must strictly comply with the safety principle. ⚫ The national and local industry related rules for safe transportation (loading and unloading) or good habits must be observed when transporting excavators.

  • Page 39: Downtime For Maintenance

    Downtime for maintenance Warning: When carrying out any maintenance work on the machine, the warning sign “No Operation” must be hung on the joystick. ⚫ The excavator must be parked on solid and flat ground. ⚫ After the excavator is stopped stably, you must lower the bucket to the ground, run the engine at idle speed for three minutes, stop it and pull out the switch key.

  • Page 40: Fire, Explosion And Poisoning Prevention

    Fire, explosion and poisoning prevention ⚫ Avoid contact with wires when the excavator is transported, walked, or excavated, otherwise it will cause serious casualties. ⚫ Excavator electrical appliances and wiring should be checked frequently. If they are found to be damaged, or aging, they must be replaced in time to prevent a short circuit of electrical wiring and causing fire.

  • Page 41: Battery

    Battery Safety rules for batteries The battery electrolyte contains sulfuric acid, which generates flammable and explosive hydrogen gas. Wrong operation can cause serious injury or fire. Therefore, the following precautions must be observed: ⚫ The battery cover is equipped with an indicator to display the battery charge state.

  • Page 42: Hydraulic System

    (hose). If any damage to the hose is found, stop the operation immediately and get in touch with the Yuchai agent. If the following problems are found, replace the hose: 1) Damaged or leaking hydraulic pipe joints;...
  • Page 43 4. Release the internal pressure of the hydraulic system The hydraulic oil in the hydraulic pipeline is at high temperature and high pressure when the machine is working intermittently. The oil may spray out when removing the oil port, so turn the oil filler cap before removing the cap to relieve internal pressure.

  • Page 44: Parts Introduction

    Parts introduction...

  • Page 45: Overview Of Controls

    Overview of controls 1. Main manual power switch (inner) 5. Right (auxiliary) pedal 9. Bulldozing pilot handle 2. Left (auxiliary) pedal 6. Instrument 10. Left pilot handle 3. Left walking joystick 7. Right pilot joystick 11. Seat 4. Right walking joystick 8.

  • Page 46: Security Lock Part

    Security lock part 1. Safety lock Warning: the security locking system of the working device is an important part of the machine safety system. When the driver leaves the cab, it must be locked safely. If the safety lock handle is not in the locked position, the handle may move, causing the working device or platform to move, which may result in an accident.

  • Page 47: Switch Assembly

    Switch assembly Switch assembly 1 for left and right control box 1. Side single frame 2. Middle single frame 3. Cover plate 4. Front work lamp switch for boom and cab shed Press the rocker switch, it is ON on the sign side, and OFF on the opposite side. 5.

  • Page 48: Electrical Control Panel

    Electrical control panel Stop position Work position Preheating position Start position Key switch 1. Key (start) switch operation Stop position: the electrical system of the whole machine stops. Work position: the electrical appliances of the whole machine work normally. Starting position: Turn the key clockwise from the starting position to the start position, and the engine start motor begins to run.

  • Page 49: Panel Meter

    Panel meter Oil level pointer Timing display Indicator area Water temperature pointer...

  • Page 50: Operation Of Working Device And Rotation Mechanism

    Operation of working device and rotation mechanism ⚫ Operation of excavation equipment and platform rotation mechanism ⚫ Operation of excavation equipment and platform rotation mechanism A. Left pilot valve handle Stick control: the stick extends when pushing upward, and retracts when pulling backward. Platform ro tatio the platform turns right when...

  • Page 51: Walking Manipulation

    ⚫ Operation of the bulldozer shovel Push the joystick down, and the bulldozer shovel cuts down. When pulling up, the bulldozer shovel is lifted. ⚫ Operation of auxiliary working devices When the machine is equipped with auxiliary working devices, the auxiliary oil source can be connected by stepping on the foot pedal of the auxiliary working device.

  • Page 52: Throttle Handle And Shutdown Handle

    Throttle handle and shutdown handle 1. Throttle handle Push the engine throttle handle forward to increase the throttle. Before stopping the engine, pull the throttle handle back to the end. 2. Shutdown handle Before stopping the engine, pull the shutdown handle back to the end.

  • Page 53: Driver's Seat

    Driver's seat Warning: accidental tipping or sudden movement of the machine may cause injury or even death. Therefore, for safety reasons, remember to fasten the seat belt and adjust the seat before starting the machine. Seat front and rear adjustment handle ●...

  • Page 54: Seat Belt

    Seat belt Warning: the seat belt is an important part of the machine safety system. Before operation, you must wear a seat belt. If you do not wear a seat belt, the cab shed or the machine may press on your body and cause injury when the machine tipped over. Warning: before using the seat belt, check the installation of the seat belt for abnormalities.

  • Page 55: Operation Guide

    Operation guide...

  • Page 56: Preparation Before Operating The Machine

    Preparation before operating the machine Excavators should be operated by trained drivers and meet the specific requirements for drivers in each region before they can be operated independently. Drivers are strictly forbidden to manipulate before reading the user guide. Drivers must wear tight-fitting and suitable clothing and relevant safety protection equipment adapted to the work before operation, such as safety helmets, leather shoes, gloves, protective glasses, seat belts, etc.

  • Page 57: Engine Operation

    Engine operation Warning: Before starting the engine, please refer to the safety details in this manual. Read all safety signs on the machine. There must be no other people in the workplace. Before operation, learn and practice safe operation. When operating the machine, you must be clear about and follow the relevant operation and maintenance sections of the manual, and comply with the corresponding laws and regulations.
  • Page 58 2. Start the engine Warning: When a warning sign prohibiting engine starting is hung on the control handle, it is not allowed to start the engine. Warning: Before starting the engine, you must confirm that the safety lock handle is in the locked position to prevent accidental contact with the joystick during starting, which may cause sudden movements of the working device and cause an accident.
  • Page 59 ⚫ Start the engine with the auxiliary cable Warning: When the battery electrolyte freezes, if (1) you try to charge, or (2) jump-start the engine, the battery will explode. To prevent the battery electrolyte from freezing, keep it fully charged. If you do not follow these instructions, you or others will be harmed. Warning: The battery generates explosive gas.
  • Page 60 The normal working temperature of hydraulic oil is 50° C~80° C. Operating the hydraulic oil below 20° C will damage the hydraulic components. Therefore, if the oil temperature is lower than 20° C before starting work, the following preheating process must be followed. 1) The engine runs at a speed greater than 200 rpm for 5 minutes.

  • Page 61: In And Out Of The Machine

    In and out of the machine 1) Make sure to hold the handrail at the cab door and the columns of four-post shed by hands, as shown in the figure. 2) Ensure that the foot is stepped on the track steadily.

  • Page 62: Movement Of The Machine

    Movement of the machine 1. Safety principles for moving machines 1) Before starting the excavator, you should be familiar with the surrounding environment of the site, whether there are pedestrians, obstacles, and ground-bearing capacity. 2) Sound the horn before starting the excavator to warn others to pay attention. 3) Drivers are strictly prohibited from standing on the ground to start and operate the machine.
  • Page 63 3. Move the machine forward 1) Put down the left control box, raise the working device and lift it 40 to 50 cm off the ground. 2) Operate the left and right walking joysticks according to the following steps. When the bulldozer shovel is in front: Slowly push the front of the joystick forward to make the machine walk forwards.

  • Page 64: Steering Of The Machine

    parking. Steering of the machine Note: Before operating the walking joystick, check the position of the bulldozer shovel. If the bulldozer shovel is behind, the operation of the walking joystick is reversed. Use the left and right walking joysticks to change the driving direction. Avoid sudden changes in direction as much as possible.

  • Page 65: Rotation Of The Machine

    Rotation of the machine ● Before turning the upper structure, check whether the surrounding area is safe. ● Confirm that the platform lock pin has been lifted and the platform and chassis have been unlocked. ● The machine platform will rotate quickly if you operate the left pilot valve handle quickly; The machine platform will rotate slowly if you operate the left pilot valve handle slowly.

  • Page 66: Operation Of Working Device

    Operation of working device The working device will move quickly if you operate the working device joystick quickly; the working device will move slowly if you operate the working device joystick slowly. The working device is operated by the left and right pilot valves. The left control pilot valve operates the stick and rotation (if a steering head is equipped, the left control pilot valve can also control the steering head to swing).
  • Page 67 4. Bucket control Operate the right pilot valve, the bucket will turn outward when it is tilted to the right, and retract when it is tilted to the left. Right working device joystick 5. Boom deflection (steering head) control Operate the left pilot valve, the steering head will turn left when it is tilted to the left, and the steering head will turn right when it is tilted to the right.

  • Page 68: Work On Slopes Or Water

    Work on slopes or water Warning: Construction near the slopes of the foothills is extremely dangerous. Rain, muddy ground, snow-covered ground, icy ground, loose sand, and soft ground, and other different working conditions bring potential dangers to operational safety. Therefore, when constructing in dangerous areas such as the foothills or slopes, you should correctly judge whether it is safe to operate in order to make a decision.

  • Page 69: Get Out Of The Muddy Environment

    Get out of the muddy environment Always be careful to avoid getting into the mud. If the machine is stuck in the mud, follow the below steps to drive the machine out. A. Track on one side is trapped Note: When lifting the machine with a boom or stick, make sure that the bottom of the bucket is in contact with the ground.

  • Page 70: Construction Work Guide

    Construction work guide 1. Backhoe operation The backhoe is suitable for digging below the machine. When the machine is in the state shown in the figure on the right, that is, when the bucket cylinder and the connecting rod, and the stick cylinder and the stick are at 90°, the maximum pushing force of the bucket can be obtained.
  • Page 71 3. Trenching operations Make the bulldozer shovel behind and anchor into the soil. Extend the boom and stick, and insert the bucket teeth into the soil. Use the stick cylinder to excavate. During the excavation process, adjust the cutting angle and loading angle of the bucket in a timely manner, or use the bucket cylinder to excavate.
  • Page 72 B. Precautions when using the bulldozer shovel The bulldozer shovel can only be used to move soil, do not use it for digging, otherwise, it will damage the bulldozer shovel or crawler system. (See the picture on the right) 2) The bulldozer shovel can't bear huge or unstable weight, otherwise, it will damage the bulldozer shovel or crawler system.

  • Page 73: Removal And Installation Of Bucket

    Removal and installation of bucket Safety principle ● When hitting the pin with a hammer, metal shavings may fly into the eyes and cause serious injury. When performing this operation, always wear goggles, helmets, gloves, and other protective equipment. ● When unloading the bucket, place the bucket steadily. ●...

  • Page 74: Park The Machine

    Park the machine Safety principle Avoid sudden parking. When parking the machine, leave as much space as possible. Park the machine on a solid and level ground. Avoid parking the machine on slopes. If it is necessary to park the machine on a slope, put a block under the track and insert the working device into the ground to prevent the machine from moving.
  • Page 75 6) Reset the parking handle after the engine stops. 7) Lock the platform. 8) Pull up the left control box by using the pilot valve safety handle, so that the machine is locked. 4-21...

  • Page 76: After Operation

    After operation 1. Check Check the engine water temperature, hydraulic oil temperature, oil pressure, fuel level, etc. on the machine's digital monitor. 2. Lock The following parts must be locked. 1) Fuel tank filler port 2) Engine hood Note: When opening the engine hood, no one can stand behind the engine hood, be careful of hurting the human body when the engine hood pops up.

  • Page 77: Loading, Unloading And Transportation Of Machines

    Loading, unloading and transportation of machines 1. Safety rules for the shipment of the machine 1) Run the engine at a low speed, and operate the machine slowly when loading/unloading. 2) Do not load/unload the machine during automatic warm-up operation. 3) If the automatic warm-up operation is cancelled during the loading/unloading operation, the speed will suddenly change.
  • Page 78 2. Loading 1) The machine can only be loaded on solid and level ground, and a certain safe distance should be kept from the edge of the road. 2) Appropriately apply brakes to the transport vehicle, and put a pad under the tire to ensure that the transport vehicle does not move.
  • Page 79 3. Fix the machine on the transport vehicle 1) Set up the working device. 2) Turn off the engine and remove the key from the start switch. 3) Lock the platform. 4) Lock the cab and engine hood. 5) Put cushion blocks under the two ends of the tracks to prevent the machine from moving during transportation, and tie the machine firmly with a steel wire rope.
  • Page 80 4. Unload the machine from the transport vehicle 1) It can be loaded and unloaded on solid and level ground, and keep a safe distance from the edge of the road. 2) The transport vehicle is braked, and a pad is placed under the tire to ensure that the vehicle does not move.
  • Page 81 1) Turn the platform so that the working device and the bulldozer shovel are in the same direction. Start the engine, adjust the working device to the posture shown in the right figure, fully raise the boom, and fully retract the stick and bucket.

  • Page 82: Working In Cold/Hot Climates

    Working in cold/hot climates 1. Work in a cold climate Cold weather will cause special problems. At this time, you must pay special attention to protection to prevent serious damage to the machine. Maintenance in cold weather will extend the life of the machine. 1) Electrical system: Keep the battery clean and fully charged.

  • Page 83: Storage Of The Machine

    Storage of the machine 1. Preparation before storage When storing the machine for a long time, follow the below steps. 1) Clean and rinse all parts, and then put the machine in the room. If you have to store the machine outdoors, choose a flat ground and cover the machine with a cover cloth.
  • Page 84 2. During storage 1) During storage, operate the machine once a month so that a new oil film is attached to the surface of the moving parts. At the same time, the battery must be charged. 2) For machines equipped with air-conditioning, the air-conditioning must be operated. 3) Rotate the track.

  • Page 85: Causes Of Technical Failures And Solutions

    Causes of technical failures and solutions Fault Reason Solution • There is a problem with the starter motor • Replace or overhaul the starter motor • Insufficient battery charge • Charge or replace with a new battery • Improper use of preheating circuit or glow plug •...
  • Page 86 Fault Reason Solution • The coolant level is too low • Add coolant • Temperature sensor failure • Replace with a new sensor • Air filter is blocked • Clean the air filter 4. The engine is overheated • The fan belt is loose or out of order •...
  • Page 87 Fault Reason Solution • Use the correct hydraulic oil • Wrong use of hydraulic oil • Oil path blocked • Consult the company's agent • Hydraulic oil filter is blocked • Clean or replace • Oil pump wear • Consult the company's agent 12.
  • Page 88 Fault Reason Solution • The track is too tight or too loose • Re-adjust • Oil pump performance is reduced • Consult the company's agent • Crawler frame deformation • Repair or replace 19. Abnormal walking • There are gravel or rocks in the track chain •...

  • Page 89: Maintenance

    Maintenance...

  • Page 90: Common Sense For Maintenance

    Check the timer on the dashboard every day to check if it is time for maintenance according to the number of working hours. Use original accessories The use of original Yuchai accessories is an important factor in ensuring the normal operation of the machine and prolonging the service life of the machine.
  • Page 91 Hazardous waste disposal Promote environmental protection and pay special attention to methods of waste disposal: ● Put the oil discharged from the machine into a container. Do not discharge the oil directly onto the ground, or pour it into sewers, drains, rivers, oceans or lakes. ●...

  • Page 92: Maintenance Summary

    Maintenance summary Lubricating oil ● Use oil that meets the grade and temperature given in the "Oil Selection Table" in this manual. In due time, the oil shall be replaced even if the oil is not dirty. ● Take care to prevent impurities (water, metal particles, dust, etc.) from entering the lubricating oil. Most of the problems of the machine are caused by the ingress of impurities.
  • Page 93 ● Electrical system maintenance: check and maintain the battery electrolyte level; Replace various bulbs; Replace fuses, relays, etc. ● Do not install any electronic components other than those specified by Yuchai Heavy Industry. ● During working on the beach, clean the electrical system carefully to prevent corrosion.

  • Page 94: Consumable Parts

    You can order the original parts from Yuchai Heavy Industry dealer according to the part number in the table or the part number in the part illustration book.

  • Page 95: Mandatory Replaceable Parts

    Mandatory replaceable parts Some parts, mainly some oil hoses play an important role in safety, and their materials are easy to age, wear or deteriorate with the working time of machine, affecting their normal functions, and becoming safe potential hazards at the same time.

  • Page 96: Oil Selection Table

    Specification for Hydraulic Oil of Hydraulic oil 46±4.5 (㎜ general area: HMP46+ Above -12 ° C Construction Machinery enterprise standard of Yuchai Heavy Industry Gear oil (GL-5) for Lubricating oil for the Universal in winter and summer SAE80W/90 heavy-duty vehicles...

  • Page 97: Tightening Torque

    Tightening torque Refer to the values in the below table for the tightening torque of each mounting bolt and nut on the machine. If the bolts or nuts are not tightened to the specified torque, the tightened or connected parts will loosen or even be damaged, causing machine failure or abnormal operation.
  • Page 98 Tightening torque of hydraulic hose Metric threaded rotary nut Outer diameter of Metric thread Nominal moment min./max steel pipe M12X1.5 15 〜25 M14X1.5 30 〜45 M16X1.5 38 〜52 M18X1.5 43〜85 M20X1.5 50〜65 M22X1.5 60〜88 M24X1.5 60〜88 M26X1.5 85〜25 M30x2 115〜155 M36x2 140〜192 M42x2...
  • Page 99 Tightening torque of hydraulic hose BSP thread and rotary nut min. / max BSPP Metric torque thread G1/4 15〜25 G3/8 27 〜41 G1/2 42 〜76 G5/8 44〜94 G3/4 95〜135 115〜165 G1.1/4 140〜280 G1.1/2 215〜365 300〜500 ORFS rotary nut UNF thread Marking line specifications 9/16〜18 11/16〜16...

  • Page 100: Regular Inspection And Maintenance Table

    Regular Inspection and Maintenance Table Regular inspections and maintenance shall be performed on the machine according to the following table, with consideration of the working hours of the machine marked by the engine timer. If the working condition of the machine is very bad or the working intensity is high, or it is equipped with accessories such as hydraulic breaker hammer, etc., the inspection and maintenance period of some parts shall be reduced.

  • Page 101: Regular Inspection And Maintenance Table (Continued)

    Regular Inspection and Maintenance Table (continued) Maintenance period (total working hours) Serial Page Inspection and maintenance details number number 1000 2000 Engine air intake system • Empty the dust container ▲ • Clean the air filter element ▲ • Replace the air filter element ▲...

  • Page 102: Routine Inspection

    Routine inspection The general routine inspection shall be carried out for the machine every day or every 10 hours. 1) Leak inspection, check whether there are oil, water and fuel leaks in various parts of the machine. 2) Check whether there are scratches, breaks or deformations on the elastic connectors and accessories. 3) Check the fixing and connection of the hydraulic device.

  • Page 103: Engine Fuel System

    Engine fuel system Maintenance instruction Tank capacity ............................... 30 liters Check oil level ..............................10 hours Drain water and impurities from oil tank ......................100 hours Clean the oil tank ..............................250 hours Check the injection pressure for ......................... 500 hours Replace the fuel filter element ..........................
  • Page 104 4. Check the oil injection pressure Check every 500 hours. The injection pressure should be checked regularly at the intervals shown in the maintenance table. Adjust if necessary. This inspection shall be carried out by our agency! The working efficiency of the engine basically depends on the working condition of the fuel injection nozzle, so it must be maintained regularly to ensure its normal operation.
  • Page 105 6. Replace the fuel filter element or the fuel filter The first replacement shall be carried out after working for 50 hours, and thereafter the filter element shall be replaced every 250 hours or every 3 months. Be sure to use the original filter element. A.

  • Page 106: Engine Cooling System

    Engine cooling system Maintenance instruction Check the coolant level ..................every day or every 10 hours of operation Check the status of rubber hoses and clamps............. every day or every 10 hours of operation Clean radiator fins ....................every 500 hours of operation Replace the coolant .....................
  • Page 107 3. Clean and inspect the radiator fins Clean every 500 hours. Dust on the outer surface of the radiator (water tank) will affect the cooling effect and shall be cleaned in time. Open the engine hood and blow away the dust or leaves and other debris that block the oil cooler fins of the radiator fins with high-pressure water or compressed air.
  • Page 108 5. Check the coolant concentration Before the cold season begins, check the concentration of the coolant. The coolant shall be able to work at an ambient temperature of minus 20 degrees Celsius. If the ambient temperature is lower, the specific gravity of the antifreeze shall be increased.

  • Page 109: Engine Lubrication System

    Engine lubrication system Maintenance instruction Oil volume ................................3.4 liters Check oil level ...................... Every 10 hours of operation or every day Change the oil or replace the oil filter element ..............Every 250 hours of operation 1. Check the oil level Check the oil level once before the new machine is put into use, and check it every 10 hours thereafter.
  • Page 110 3) Clean the drain plug and reinstall it. If the seal ring is damaged, replace it. 4) Open the oil filler port. 5) Refill with new oil until the oil reaches the "Maximum" mark H on the oil dipstick. 6) Cover the oil filler cap and allow the engine to idle for 5 minutes.

  • Page 111: Engine Air Intake System

    Engine air intake system Maintenance instruction Cleaning cycle of dust tank ..............Every 10 hours or every day Cleaning cycle of air filter element Every 100 hours of operation ..............Replacement cycle of air filter element ........... Every 500 hours of operation 1.
  • Page 112 Note: Before installing the cleaned filter element or replacing it with a new one, check whether the filter element is damaged. Method: Place a light source inside the filter element to check whether there are holes in the filter element. The filter element cannot be used if holes are found. 3.

  • Page 113: Other Maintenance For Engine

    Other maintenance for engine Warning: To prevent injury, do not maintain the engine while the engine is running. If maintenance must be performed while the engine is running, the operation shall be performed with at least two people and the following regulations shall be followed: One person shall sit in the operator’s seat and ready to shut down the engine at any time.

  • Page 114: Hydraulic System

    Hydraulic system Maintenance instruction Hydraulic oil tank capacity ......................... 25 liters Check the oil level ............................every 10 hours Change filter element ..........................every 2000 hours Change the hydraulic oil ..........................every 2000 hours Check the system pressure ........................every 400 hours Warning: If hydraulic oil or grease is injected into the skin, which may cause serious injury and death.
  • Page 115 2. Remove the water and dirt from the hydraulic oil tank Drain the water and dirt from the hydraulic oil tank every 250 hours. 1) After stopping the machine until the oil temperature drops or before starting work every day, discharge the air from the oil tank.
  • Page 116 14) In order to pressurize the hydraulic oil tank to retract the piston rod of the hydraulic cylinder. Note: The oil level in the hydraulic oil tank will be slightly increased after this last operation. Replace the hydraulic oil return filter element The first replacement shall be carried out after working for 2000 hours, and thereafter it shall be done every 2000 hours.
  • Page 117 D. Discharge the air in the rotary motor (when the oil in the housing of the rotary motor is discharged) Note: During the exhaust, the machine cannot be rotated under any circumstances. 1) Run the engine at idle speed, loosen the exhaust plug, and check whether the oil flows out from the exhaust plug.
  • Page 118 5. Replace the oil return filter element Air filter (fuel filler port) Oil return filter The first replacement shall be carried out after working for 2000 hours, and thereafter it shall be done every 2000 hours. The oil return filter is in the Hydraulic oil hydraulic oil tank, so: dipstick...
  • Page 119 ◼ The replacement cycle of hydraulic oil and filter elements during using accessories (such as breaker hammer) Since if the hydraulic hammer is used, the pollution of the hydraulic system is increased and corrosion is accelerated. Compared with excavating devices, the replacement cycle of hydraulic oil and filter elements shall be shortened accordingly, so as not to damage the hydraulic pump and other hydraulic components.

  • Page 120: Battery

    Battery Warning: 1) The battery contains sulfuric acid liquid, which is highly corrosive. Please keep it away from children. Users should wear protective glasses and rubber gloves when operating the battery. Once the eyes, skin and clothes are splashed with sulfuric acid, wash them with plenty of water immediately, and go to the hospital for treatment in serious cases.
  • Page 121 (generally more than 15 days). The battery shall be recharged every 3-6 months (depending on whether the indicator is black). 5) For the battery in question, please contact Yuchai Heavy Industry dealer in time to solve it. 5-33...

  • Page 122: Reducer

    Reducer Maintenance instruction Rotary reducer lubricating oil capacity ................... 0.5 liters Rotary reducer lubricating oil capacity ................... 1 liters (each side) Check the lubricating oil level and add oil ................every 250 hours of operation Change the lubricating oil ...................... every 1000 hours of operation Check the tightening torque of the connecting bolts of the reducer ........
  • Page 123 2. Replace the lubricating oil (for each reducer) The first replacement shall be carried out after 1000 hours working for a new machine, and thereafter it shall be done every 1000 hours. 1) Park the excavator on level ground. 2) Rotate the reducer to make the 3 screw plugs on its outer end perpendicular to the ground, and then stop the machine.

  • Page 124: Track

    Track Check and adjust the tension of the track Check every 10 hours. 1) Park the excavator on a level and solid ground. 2) Put the bulldozing board at the back and fully extend the piston rod of the bulldozing cylinder until the crawler is slightly lifted.

  • Page 125: Thrust Wheels, Supporting Wheels And Guide Wheels

    Thrust wheels, supporting wheels and guide wheels 1. Check the tightening torque of the thrust wheels The first inspection after working for 50 hours and then every 500 hours. The tightening torque of bolt ① shall be 110N·m. If the bolts loose, unscrew the bolts, remove the thread locking agent between the bolt threads, and then apply 1.

  • Page 126: Lubrication

    Lubrication Lubricate the lubrication points of the machine every 50 hours. Lubrication steps: 1) Start the working device and put the bucket on the ground. 2) Put the bulldozer shovel on the ground. 3) Stop the engine. 4) Wipe up the filling nozzles of each oil cup. 5) Lubricate each lubrication point and wipe off excess grease squeezed out.
  • Page 127 Note: 1) If there is abnormal noise in the lubrication area, the additional lubrication beyond the maintenance interval is required. 2) When operating the machine for the first 50 hours, lubricate it every 10 hours. 3) If the excavation operation is carried out in water, lubricate the pin immersed in water before and after the operation.

  • Page 128: Bucket Teeth Replacement

    Bucket teeth replacement Replace the bucket teeth before the bucket teeth base is worn. Warning: When replacing the bucket teeth, it is very dangerous if the working device moves accidentally due to wrong operation. Therefore, before replacing the bucket teeth, put the working device in the locked state, then shut down the engine and lock all joysticks firmly.

  • Page 129: Washing Of Floor Mats

    Washing of floor mats If the floor rubber mats are dirty, clean them at any time to prevent accidents due to slipping and falling of the floor. Warning: If you accidentally touch the joystick, the working device or machine will suddenly move, causing serious accidents.

  • Page 130: Accessories Guide

    Accessories guide...

  • Page 131: Safety Precautions

    Safety Precautions If you install accessories or options that are not approved by Yuchai, it will not only affect the service life of the machine, but also cause some safety problems. During installing accessories that are not approved by Yuchai, please contact Yuchai dealer in advance.

  • Page 132: Assembly/Disassembly Steps Of Accessories

    Assembly/disassembly steps of accessories 1. Disassembly steps 1) Put the accessories on the ground and turn off the engine. 2) Turn the start switch to the ON position and push the left control box to the free position. 3) Operate each working device joystick and accessory control pedal 2 to 3 times forward, backward, left and right in full stroke to eliminate the internal pressure in the hydraulic oil circuit.

  • Page 133: Accessories Operation Guide

    Note: Select the most suitable accessory for the main engine. The models of machines that can install accessories are different. For the selection of accessories and machine models, please contact your Yuchai dealer. Hydraulic breaker hammer 1. Guidelines for the use of hydraulic breaker hammer Hydraulic breaker hammer is the most common work accessory.
  • Page 134 4) Make sure that the drill rod always impact the surface properly to prevent the impact force from being used if there is no resistance. If the rock or the target has been crushed, stop the action of the breaker hammer immediately. The continuous aimless impacting will cause the front part and the main bolts to loosen and damage, and even damage the excavator itself.
  • Page 135 3) The drill rod is moved during impact operation. 4) Apply impact force horizontally or upward 5) Swing the breaker hammer after it has penetrated the rock 6) Pecking operation...
  • Page 136 7) Carry out crushing operations in water or muddy ground 8) Use the breaker hammer as a tool for lifting heavy objects. 9) The bucket cylinder is fully extended to lift the machine off the ground.

  • Page 137: Daily Inspection Of Hydraulic Breaker Hammer

    Daily inspection of hydraulic breaker hammer Carry out the daily inspection and maintenance of the hydraulic breaker hammer according to the following table. Inspection or Check points Maintenance method Serial maintenance items number Check whether the bolts and Body bolts and side plate bolts Tighten the bolts or reinstall new bolts nuts are loose or missing Check the hose parts for...

  • Page 138: Quick Coupler

    Quick coupler 2) Pry up with a crowbar ①. 2) Put the bucket pin into ②③, put down the crowbar, and the bucket is installed. 2. Unloading the bucket 1) Pry up ① with a crowbar. 2) Unload the bucket.

  • Page 139: Grab Bucket

    Grab bucket The grab buckets are used for digging or loading on one side of a ditch or confined space. It is applicable to the foundation works such as cleaning up the sundries in the sewage ditch and dredging the passageway of the upper and lower sewers.
  • Page 140 3) Do not use a grab bucket to crush stones or cut into the soil. 4) Do not use grab bucket to drive or pull piles. 5) Before leaving the machine, open the grab bucket and lower it to the ground. Note: remove the grab bucket from the stick when transporting the machine.

  • Page 141: Drilling Device

    Drilling device 1. Installation of drilling device 1) Remove the bucket or other accessories. 2) Put the accessory on a flat place, and connect the stick to the drilling device and the connecting rod to the drilling device with pin A and pin B in turn. 3) After confirming that the oil temperature has decreased, remove the plugs from the outlet and inlet respectively.
  • Page 142 3. Precautions for operation of drilling device Please make sure that the direction of the drill bit is perpendicular to the working surface when drilling and keep this state as far as possible. If it is inclined to the working surface, the drilling tool will be damaged in this case.

  • Page 143: Backhoe Bucket With Scraper

    Backhoe bucket with scraper 1. Backhoe bucket installation It is installed in the same way as the bucket. 2. Operation of the backhoe bucket By operating the handle of the right pilot valve, the scraper of backhoe bucket will retract inwards and the backhoe bucket will turn outwards when swinging to the right, the scraper of backhoe bucket will push outwards and the backhoe bucket will retract inwards when...
  • Page 144 Guangxi Yuchai Heavy Industry Co., Ltd. SJ008/U27-AF51-2022 Publication Date: March 2022 Address: No. 168, Tianqiao Road, Yulin City, Guangxi, China (537005) Phone: 95105432...

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