FAQs

We are specialized in excavator spare parts, such as travel motor gearbox assy & parts, swing gearbox motor assy & parts, and hydraulic pump motor assy and spare parts. If any are needed, we can also supply them as per your requirements.

Yes, we sell parts and have a repair team to offer support.
1. Software solution.
A. ECU & Monitor Reprogram
B. DPF Program Solution
C. Software refit

2. Engine Rebuild & Testing
Maintenance Team Support
A. ET for Caterpillar Diagnosis
B. Inline 6 for Cummins/Komatsu/Hyundai Diagnosis
C. IDSS for Hitachi/Isuzu/Case/Sany/Sumitomo/JCB/XCMG/Isuzu Truck Diagnosis
D. DX2/NEXIQ for Kobelco/Hino truck Diagnosis
E. Vocom for Volvo/Volvo truck/Penta Diagnosis
F. DST-i for KUBOTA DENSO Diagnosis

3. hydraulic Remanufacture & Testing
A. Offer new or rebuilt hydraulic pump & motor
B. Control valve & main pump repair & rebuild knowledge
C. Offer stable and cheap hydraulic test machines
D. All rebuild valves, pumps, and motors offer testing video for cilent

Yes, excavator model, old photos, and size are also available to confirm the correct parts you need.

By sea, air or by express ( DHL, Fedex, TNT, UPS, EMS)

We can accept payment by T/T, Trade Assurance, Paypal, or Western Union.

1. Kyotechs, Focus on the machinery industry over 20 years, have abundant experience and sound reputation in the field. support the full range of excavator accessories.
2. kyotechs offer Maintenance service: repair and testing for monitor ECU controller software; Engine start testing, remanufacture and repaint; Hydraulic pump refit, etc.
3. 100% quality guaranteed; Kyotechs offers different quality requirements for excavator parts. new and used genuine parts, OEM parts made in China, Japan, Korea. main parts normal operation running at least 3-5 years. Use Kyotechs parts; few worries!
4. Small orders and sample orders are acceptable; large quantities and price negotiations.
5. Quick delivery time: order before 4:00 p.m. and ship out on the same day.

There are usually the highest and lowest oil level marks (MAX and MIN) on the inner wall of the oil filling port of each engine. This means that the oil level cannot exceed MAX or be lower than MIN.

A lower oil level, that is, a decrease in the amount of oil in the engine, will increase the oil load, causing the oil to become more seriously contaminated by heat, which not only weakens the lubrication performance, but also increases the fuel consumption. Because the less oil in the engine, the higher the oil temperature; and the higher the oil temperature, the greater the fuel consumption will be as the oil temperature rises. It is very dangerous to run the engine when the oil level is at the lowest point (MIN).

Keeping the oil level at the highest point (MAX) all the time will cause the oil to foam and lead to insufficient lubrication, resulting in serious wear. Foaming oil will also increase fuel consumption.

Therefore, it is recommended to keep the engine oil level between the MAX and MIN marks at a position close to one-third of the MAX.

When the engine replaces new piston rings, pistons or cylinder liners, due to the initial poor running-in, it is easy for the engine oil to enter the combustion chamber and burn, producing blue smoke. This phenomenon can generally be gradually eliminated after running for 8-10 hours.

(1) The oil level in the oil pan is too high.

(2) The engine oil in the air filter leaks into the combustion chamber from the intake pipe and burns.

(3) The piston ring is bonded to the piston ring groove by carbon deposits, causing the engine oil to leak into the cylinder and burn.

(4) The piston ring is excessively worn, or when several piston rings are installed, the opening gap has been matched.

(5) The matching clearance between the piston and the cylinder liner is too large.

(6) The piston ring is not elastic enough.

Digging powerlessness can be divided into two situations: one is digging powerlessness, the engine does not hold back, and the load feels very light; the second is digging powerlessness, when the boom or dipper stick is extended to the bottom, the engine is seriously held back or even stalled.

①, digging powerlessness but the engine does not hold back. The magnitude of the digging force is determined by the output pressure of the main pump, and whether the engine holds back depends on the relationship between the oil pump absorption torque and the engine output torque. The engine does not hold back, indicating that the oil pump absorption torque is small and the engine load is light. If the working speed of the excavator is not obviously abnormal, the maximum output pressure of the main pump, that is, the system overflow pressure, should be checked in particular. If the overflow pressure measurement value is lower than the specified value, it indicates that the overload overflow valve setting value of the hydraulic circuit of the mechanism is incorrect, resulting in premature overflow of the mechanism and powerlessness. The machine can be adjusted by turning the adjustment screw.

②, digging powerlessness, engine holding back. The engine holding back indicates that the absorption torque of the oil pump is greater than the engine output torque, causing the engine to overload. This fault should first check whether the engine speed sensing system is normal, and the inspection method is similar to the engine inspection method described above. After the above detailed inspection and troubleshooting, the engine speed sensing system will resume normal function, the engine stalling phenomenon will disappear, and the digging force will return to normal.

8 reasons for the engine speed drop of the excavator, 6 solutions are here!

As the name suggests, engine speed drop means the failure of the engine speed drop during the operation of the excavator. There are two manifestations of speed drop, one is a slight speed drop within 200 revolutions, and the other is a serious speed drop above 300 revolutions, which is likely to cause the excavator to suddenly shut down. There are 8 main reasons for the engine speed drop of the excavator.

1. The diesel oil circuit of the excavator is faulty. Generally speaking, when the diesel oil circuit is blocked, it may cause the speed drop phenomenon.

2. The hydraulic system of the excavator has a fault, so that the hydraulic pump cannot change the displacement normally, causing the system pressure to be too high, and the speed drop may also cause a machine failure.

3. The output power of the excavator engine itself is insufficient, the output power is lower than the rated power, and the speed is too low. There is also a problem with the main pump.

4. The engine uses fuel of poor quality or the water content of the fuel is too high, which will lead to insufficient engine power and speed drop.

5. When the air intake system leaks or is blocked, the engine will be short of air supply, resulting in incomplete combustion of fuel, and there will be speed drop and black smoke failure.

6. Due to the large gap of the solenoid valve, the fuel supply is insufficient, which causes the engine to drop.

7. The joint of the fuel supply circuit of the fuel system is loose or the pipeline is broken, causing fuel leakage or foreign matter blockage, resulting in insufficient fuel supply. In addition to speed drop, it may also cause flameout.

8. There are many reasons for speed drop, such as incorrect valve clearance, wrong injection timing, damaged turbocharger, faulty brakes, etc.

Having said so many reasons for the speed drop of the excavator engine, what should we do when the speed drop occurs?
The solutions are all here!

1. First, check whether the diesel used in the excavator is deteriorated, whether there are impurities in the oil, and whether the oil circuit is blocked.

2. Check the valve clearance of the excavator engine and the speed of the engine.

3. Check the intake pipeline, clean the air pre-filter and air filter element, and start the engine again.

4. Check whether the speed drop of the excavator occurs when the engine is under load?

5. Carefully check the engine to see if the engine failure causes the speed drop of the excavator engine.

6. In addition, the electronic control, hydraulic system, fuel system, etc. need to be checked.

Kobelco excavator maintenance tips 1: Cooling to prevent air blockage In high temperatures in summer, the engine is prone to air blockage due to high speed and difficult heat dissipation, which makes it difficult to start the engine after stopping for a few minutes. Once air blockage occurs, the excavator driver should stop the engine immediately to cool down and eliminate the fault.

Kobelco excavator maintenance tips 2: Observe the water temperature gauge at any time to prevent water shortage When driving in high temperature weather, always pay attention to checking the cooling water volume and the water temperature gauge. When water shortage is found, immediately idle the engine to cool down before adding water, and be careful not to open the radiator cap immediately to prevent burns.

Kobelco excavator maintenance tips 3: Prevent engine oil from deterioration Lubricating oil is easily diluted by heat, resulting in poor oxidation resistance, easy deterioration, and even causing faults such as burning of the bearing and the shaft. Therefore, the crankcase and gearbox should be replaced with summer lubricating oil, and the amount and quality of the lubricating oil should be checked frequently, and replaced in time.

Kobelco excavator summer maintenance tips 4: timely cleaning of engine surface oil If the external oil of the engine is too thick, it will affect the heat dissipation and bury the hidden danger of failure of various parts. You can use the high-pressure spray method to clean the engine parts with a cleaning agent that does not corrode the body parts.

Kobelco excavator summer maintenance tips 5: prevent the water tank water temperature from being too high In summer, the cooling water of Kobelco excavators evaporates and consumes quickly. You must add enough cooling water before leaving the vehicle, and check the water level frequently during work. For single-cylinder diesel engines without a water temperature gauge, always pay attention to the red mark height of the water tank float. If the float cannot be used normally, it should be repaired in time. If the boiling phenomenon occurs during work, do not add cooling water directly. Stop the work, slow down the generator, and slowly add cooling water after the water temperature drops to avoid cracks in the water tank when it is cold.

Kobelco excavator summer maintenance tips 6: Ensure the best oil supply time In summer, the oil supply time of Kobelco excavators should be adjusted. If the oil is supplied too early, the engine will make a knocking sound and sometimes reverse; the oil supply time should not be too late, otherwise the engine will work weakly.

Kyotechs specializes in providing a wide range of parts for excavators and heavy equipment, including hydraulic pumps, engine parts, electronic controllers, drivetrain components, travel gear, oil seals, filters, etc. They provide spare parts for many makes and models of excavators.

Kyotechs is an active participant in social media channels. Facebook, whatsup, Twitter, Instagram, YouTube and LinkedIn are powerful tools that allow us to connect with customers, investors, potential employees and fans.

In the field of modern engineering machinery, excavators play a vital role, and behind this, there is a company that is quietly adding momentum to the industry, that is Kyotechs. With the mission of "building a community of shared destiny for partners and adding strength to the excavator industry", Kyotechs is not only committed to providing high-quality excavator parts, but also promoting the development of the entire industry with a long-term vision and innovative thinking.

In an increasingly competitive market environment, the era of fighting alone is over, and win-win cooperation is the key to future development. Therefore, the company has always been committed to building a close community of shared destiny for partners. This is not just a simple business cooperation, but also a deep collaboration based on trust, mutual assistance and common goals.

In this community of shared destiny, Kyotechs shares information, resources and opportunities with suppliers, customers, technical partners and other relevant parties. In this way, the company can not only respond quickly to market needs, but also foresee and respond to industry challenges in advance. The success of our partners is our success. It is this concept of symbiosis and win-win that has established a good reputation for Kyotechs in the industry.

As a company focusing on excavator parts, Kyotechs' products cover hydraulic pumps, engine parts, electronic controllers, transmission system parts and other fields. These high-quality parts not only ensure the efficient operation of the excavator, but also play an important role in improving overall engineering efficiency and reducing equipment failures.

Kyotechs not only pursues commercial success, but also takes "becoming a happy person in the field of excavation equipment" as its vision, emphasizing the happiness and satisfaction of all stakeholders. This vision reflects the company's deep care for employees, customers and society.

For Kyotechs, customer satisfaction is an important criterion for measuring our success. The company has always been customer-oriented and provides high-quality products and a full range of services. Whether it is product quality, delivery speed or after-sales service, Kyotechs strives to do its best to ensure that every customer can enjoy an experience beyond expectations.

1. Chain off caused by tension cylinder failure
At this time, you should check whether you have forgotten to butter the tension cylinder and see if there is any oil leakage in the tension cylinder.

2. Chain off caused by severe wear of the crawler
If used for a long time, the crawler will definitely be worn, and the wear of the chain ribs, chain barrels and other parts on the crawler will also cause the crawler chain off.

3. Chain off caused by wear of the chain guard
Now almost all excavator crawlers have chain guards, and chain guards can play a very important role in preventing chain off, so it is also very important to check whether the chain guard is worn.

4. Chain off caused by wear of the drive motor ring gear
For the drive motor ring gear, if it is severely worn, we need to replace it, which is also an important reason for the excavator chain off.

5. Chain off caused by damage to the sprocket wheel
Generally speaking, oil leakage of the sprocket wheel oil seal of the excavator will cause severe wear of the sprocket wheel, which will cause the crawler chain off. The public account Zhizao Daguan focuses on sharing relevant theoretical knowledge in the engineering machinery manufacturing industry.

6. Chain derailment caused by guide wheel damage
When checking the track guide wheel, check whether the screws on the guide wheel are missing or broken. Check whether the groove of the guide wheel is deformed.

1. When walking on the construction site, please try to place the travel motor behind the walking to reduce the squeezing of the sprocket.

2. The continuous walking time of the machine cannot exceed 2 hours. The walking time on the construction site should be minimized. If necessary, it is recommended to walk after a short stop in the middle.

3. Avoid raised hard objects when walking to avoid stress concentration on the track chain.

4. Confirm the tightness of the crawler, adjust the crawler tighter in soft places such as soil, and adjust the crawler looser when walking on stones. It is not good to have a crawler that is too loose or too tight. Too loose will cause the crawler to derail easily, and too tight will cause the chain sleeve to wear too quickly.

5. Check whether there are foreign objects such as stones in the crawler frequently, and clean them if there are.

6. When working on a muddy construction site, it is necessary to frequently idle to discharge the soil deposited in the crawler.

7. Try to avoid the excavator turning in circles on the spot.

8. Regularly check the rail guard and the rail guard welded under the guide wheel.

We need a fulcrum. Our fulcrum is the excavator bucket. The bucket can easily lift the excavator body, and then according to the different situations of the crawler derailment, the crawler can be installed back by using the tacit cooperation of the bucket and the walking.

Distilled water should be added. Because the battery will generate heat during the charging and discharging process, the water will evaporate, and the specific gravity of the electrolyte will increase. After adding distilled water, the specific gravity of the electrolyte can be restored.

The role of the battery (battery) is to supply the short-term huge discharge current (300-500A) required for the starter motor. When the generator does not generate electricity, or the generator generates insufficient electricity at low speed and the generator is overloaded, it can supply power to the electrical equipment. It can also convert the electrical energy provided by the generator into chemical energy and store it, and then supply power to the electrical equipment.

The batteries we use are all lead-acid batteries for starting. Because this type of battery has the characteristics of large starting current and can meet the power supply requirements of the starter motor.

When the battery liquid specific gravity is lower than 1.15 or the single cell voltage is lower than 1.7V (V), or when changing seasons for maintenance, it should be removed for recharging and the liquid specific gravity should be adjusted. If it needs to be parked for a long time, it should be fully charged and stored, and recharged once a month. If it needs to be stored for a long time, it should be fully charged, all the liquid should be poured out, and the filling port should be sealed for storage. When it needs to be used, re-add the electrolyte that meets the requirements.

After the newly purchased battery is injected with the liquid with the appropriate specific gravity, it should be placed for 6-8 hours to allow the liquid to penetrate the plates. When the temperature of the liquid drops below 30℃, it can be charged for the first time. The initial charge should be carried out in two stages. The charging current in the first stage should be lower than 1/10 (one tenth) of the rated capacity of the battery, and the time is about 25-35 hours. When the voltage of a single cell rises to 2.4 volts, the current is reduced by half and the second stage is entered, which takes about 20-30 hours. When the electrolyte emits strong bubbles and the specific gravity no longer rises, the voltage of a single cell rises to 2.6-2.75 volts and remains unchanged for 2-3 hours, it means that the battery is fully charged. During charging, the temperature of the electrolyte will rise, exceeding 40℃ in summer and 35℃ in winter. Charging should be suspended and recharged when the temperature drops below 30℃ to prevent damage to the plates and separators.

Connecting the terminals of the same polarity of each battery together is called parallel connection. Its characteristics are: the voltage is the same as the voltage of a single battery, and the current flowing out is equal to the sum of the currents flowing out of each battery. (The voltage remains unchanged, and the current increases). Connecting the opposite-polarity terminals of each battery in sequence is called series connection. Its characteristics are: the total voltage is the sum of the voltages of each battery, and the current flowing out is the same as the current flowing out of each single battery. (The current remains unchanged, and the voltage increases).

1.The climate is cold in winter, the ambient temperature is low, the viscosity of the engine oil increases, and the friction resistance of each moving part increases, which reduces the starting speed and makes it difficult to start.

2.The battery capacity decreases as the temperature drops, which further reduces the starting speed.

3.Due to the reduction in starting speed, the leakage of compressed air increases, and the heat dissipation of the cylinder wall increases, which greatly reduces the temperature and pressure of the air at the end of compression, and increases the delay period of diesel ignition. In severe cases, it may even fail to burn.

4.The viscosity of diesel at low temperatures increases, which reduces the injection speed. In addition, the swirl speed, temperature and pressure of the air at the end of compression are relatively low, which makes the atomization quality of the diesel injected into the cylinder poor, making it difficult to quickly form a good combustible gas with the air and ignite and burn in time, or even fail to ignite, resulting in difficulty in starting.

1. There must be enough starting speed. The high starting speed means less gas leakage in the cylinder, shorter heat transfer time of compressed air to the cylinder wall, less heat loss, and higher gas temperature and pressure at the end of compression. Generally, the speed is required to be above 100r/min.

2. The cylinder should have good sealing. This can further reduce the amount of leakage and ensure that the gas has sufficient combustion temperature and pressure at the end of compression. The compression pressure of the cylinder shall not be lower than 8_0_%_ of the standard value.

3. The engine is required to have appropriate clearance relative to the running parts and good lubrication.

4. The battery must have sufficient starting capacity and the technical condition of the starting circuit is normal.

5. The starting oil volume meets the requirements, the injection quality is good, and the injection advance angle meets the requirements.

6. Use fuel that meets the requirements

1. The starter and flywheel teeth are not meshed well. The ring gear and the starter gear collide when starting the engine, causing tooth damage or single-sided wear of the teeth. If more than three teeth are damaged or worn seriously, it will be difficult for the starter gear and the ring gear to mesh.

2. Cylinder sticking. When the engine temperature is too high, the engine is stopped and the heat is difficult to dissipate. The piston ring at high temperature sticks to the cylinder and cannot start after cooling.

3. Crankshaft lock. Due to lubrication system failure or lack of oil, the sliding bearing rubs dry, which eventually locks the crankshaft and cannot start.

4. The injection pump plunger is stuck.

1.There is no oil in the fuel tank.

2.The fuel filter and oil-water separator are blocked.

3.The low-pressure oil circuit does not supply oil.

4.The injection pump does not pump oil.

5.There is air in the oil circuit.

6.The valve timing is misaligned. The opening time of the valve is not coordinated with the stroke of the piston in the cylinder. For example, when the piston makes a compression stroke in the cylinder, the intake and exhaust valves are open, and fresh air is driven out of the cylinder, so that there is no combustion gas in the cylinder and it cannot start.

7.The solenoid valve of the injection pump is broken and is in a closed state, and the diesel cannot enter the high-pressure chamber.

The pump housing will wear more in the oil inlet chamber. If the pump housing is symmetrical, it can be turned 180 degrees. Then use it. For the passive gear, the two ends cannot be replaced. Make a mark when removing it. Because the gear will wear on one side. The active gear is integrated with the rotating shaft and cannot be turned over; turning the passive gear over can change the contact point of the meshing line of the two gears. After the pump is assembled, add a little lubricating oil and rotate it slightly by hand. The feel should be smooth.

It can only be found when assembling the gear pump, because the end face clearance is very small, generally around 0.05mm. If the perpendicularity between the end face and the bearing hole has changed, the gear shaft cannot move after the pump is assembled. If the locking screw is loosened a little, but it still does not turn smoothly, and the gear pump is disassembled and inspected, there are scratches on the end face. This is caused by the end face plane not being perpendicular to the bearing hole.

This is because the valve plate was over-ground during maintenance and the grinding amount was too much, so the pressure between the valve plate and the cylinder plane is insufficient. At low throttle, the oil pressure is small, and it is not easy to leak between planes; at high throttle, the oil pressure increases, and overflow occurs between planes, causing the track to be unable to move at high throttle. The remedy is to add a gasket to the spring. If it is a butterfly spring, you can add an extra butterfly spring.

1. Most of the white smoke is caused by water in the cylinder. Please check whether there is water in the excavator diesel. Generally, the white smoke is emitted for a short time after starting, and there is no problem with the engine;
2. If the excavator starts to emit white smoke, the oil is not reduced, and the excavator works weakly, it means that the cylinder mattress of the excavator engine is worn;
3. Poor atomization of the injector and low cylinder pressure are also one of the reasons for the excavator engine to emit white smoke. Check the injector.

Blue smoke when starting a cold car: It is normal for a cold car to emit blue smoke and disappear after the car is heated, because a small amount of oil will invade the engine combustion chamber after the shutdown. Continuous blue smoke after starting:

1. The diesel filter is clogged, check whether the oil type is correct;

2. The engine piston ring and valve oil seal are worn, affecting the oil in the intake or exhaust pipe, which causes the excavator to emit blue smoke;

3. The clearance between the piston and the cylinder liner is too large, causing blue smoke;

1. 1. Insufficient air intake: Check whether the intake valve clearance is within a reasonable range. Unequal valve clearance will cause insufficient intake pressure and volume; whether the air filter is clogged. The supercharger is damaged, resulting in insufficient intake pressure;

2. The diesel quality is poor, and the diesel pump and fuel injector are worn;

3. Injector wear: Excessive fuel injection leads to incomplete combustion. Service personnel are required to perform an engine cylinder disconnection experiment to check whether it is caused by wear of the fuel injector.

Reasons from the piston group
1. The piston ring gap is too small. If the opening gap, side gap or back gap of the piston ring is too small, the piston ring will be stuck due to heat expansion when the engine is working, and it will be pressed tightly against the cylinder wall, or the piston ring will be broken, which can easily pull out grooves on the cylinder wall.
2. The piston pin is out. Because the piston pin retaining ring is not installed or falls off or breaks, the piston pin will be out during movement, which can easily damage the inner wall of the cylinder and cause the cylinder to blow into the crankcase.
3. The piston cylinder gap is too small or too large. If the piston material is poor, the manufacturing size error is too large, or the piston is deformed after the piston pin is assembled, the matching gap between the piston and the cylinder is too small, and the piston is stuck after heat expansion, which will then damage the cylinder wall.
4. The piston ring is seriously carbonized. Excessive carbon deposits cause the piston ring to stick or bite in the ring groove. At the same time, carbon deposits are a hard abrasive that will grind into longitudinal grooves on the cylinder wall.
5. The piston is seriously off-cylinder. Due to the bending and twisting of the connecting rod, the parallelism and coaxiality deviations of the connecting rod journal, main journal, and piston pin seat are too large, causing the piston to be significantly off-cylinder, which will accelerate the wear of the piston ring, piston and cylinder wall and destroy the formation of the oil film.

Reasons for cylinder sleeves
1. The roundness and cylindricality tolerances of the cylinder sleeves exceed the allowable range, which greatly reduces the sealing of the piston and cylinder sleeves. The high-temperature gas in the cylinder flows down, destroying the oil film between the piston and the cylinder wall, and then causing cylinder pulling.
2. The cylinder sleeve is deformed during the assembly process. For example: the protrusion of the upper end surface of the cylinder sleeve is too large, and the cylinder sleeve is deformed after the cylinder head is installed; the cylinder sleeve water blocking ring is too thick, and the cylinder sleeve is deformed after being pressed into the body, which can easily cause cylinder pulling.

Reasons for use:
1. Whether the size of the cylinder sleeve used during assembly does not match the cylinder body and piston.
2. The air filter is not sealed, which makes the filtering effect worse. Dust, sand and other impurities in the air are sucked into the cylinder, forming abrasive wear. Tests show that if a few grams of dust are sucked in every day, the wear of the cylinder liner will increase by more than 10 times.

To check if the hydraulic system is functioning properly, observe the color and viscosity of the hydraulic oil, check the oil level in the hydraulic tank, look for leaks in the lines and fittings, and test the output pressure of the hydraulic pump.

First, park the excavator on a flat, safe surface, shut off the engine, and release the system pressure. Then, open the drain plug on the hydraulic tank to drain the old oil. Replace the filters, refill with new hydraulic oil, start the engine, run the system to expel air, and check the oil level.

To adjust the track tension, refer to the specific operation manual for the excavator model. Generally, this is done by adjusting the bolts on the tension cylinder or increasing/decreasing the pressure of the tension spring.

If the tracks are severely worn, they should be replaced promptly to avoid further damage and safety hazards. Ensure that the new tracks match the specifications of the original tracks and are installed correctly.

Abnormal noises from the hydraulic pump may be due to air entering the hydraulic system, contaminated hydraulic oil, or internal wear of the hydraulic pump. Check the condition of the hydraulic oil, inspect the suction line for leaks, and replace the hydraulic pump or related components if necessary.

Swing system issues are usually related to the hydraulic motor, swing gears, or control valves. First, check the operation of the hydraulic motor, inspect the gears for wear, and ensure the control valves are working properly. Replace faulty parts as needed.

Testing engine performance includes checking the engine's start-up, running, acceleration, and emissions. Use diagnostic equipment to read engine fault codes, test the fuel system and ignition system, and regularly conduct compression tests and exhaust analysis.

Engine overheating may be caused by low coolant levels, clogged cooling system, or water pump failure. Check the coolant level, clean the radiator, inspect the water pump and fan, and replace faulty parts as necessary.

After the machine has cooled down, locate the filters that need to be replaced (such as oil, fuel, and air filters). Use tools to remove the old filters, clean the installation area, install the new filters, and ensure they are sealed properly.

To address oil leaks, inspect seals, fittings, and lines. Locate the leak, tighten any loose fittings, and replace worn or damaged seals and lines. Clean the area and recheck for leaks.

Use a multimeter to check circuits, inspect fuses and relays, test the battery voltage and charging system, and check the control panel and sensors. Replace faulty components as necessary.

Regularly check and replace air filters, clean the air filter housing, ensure the intake lines are not clogged, and inspect the air filtration system for proper sealing to prevent dust from entering the engine.

Start the excavator and let the hydraulic system run for a while. Operate all hydraulic functions to expel air, check the hydraulic tank oil level, and add hydraulic oil to ensure the system is full.

Check the battery charge and connections, inspect the starter motor and ignition system, ensure the fuel system is supplying fuel properly, and read fault codes for further diagnostics.

Check the hydraulic pump, pressure control valve, and hydraulic cylinders. Test the hydraulic oil for contamination or degradation, clean or replace relevant components, and ensure the hydraulic system is properly sealed.

Regularly lubricate the swing bearing, check if the grease is sufficient, inspect the bearing for wear or looseness, and adjust or replace it if necessary.

Inspect the tracks, travel motors, and travel reducers. Test the pressure and flow of the hydraulic drive system, check if the control valves are functioning correctly, and perform necessary repairs or replacements.

Check the hydraulic system pressure, inspect control valves and hydraulic cylinders for leaks or wear, clean or replace hydraulic filters, and replace hydraulic oil if necessary.

Check and clean the fuel filters, clean sediment from the fuel tank, inspect the fuel lines for blockages or leaks, and use appropriate cleaning agents to flush the fuel system.

Before long-term storage, perform a thorough inspection and maintenance, drain fuel and hydraulic oil, lubricate all parts, start the engine periodically to run the system, and ensure all systems operate correctly.

To diagnose a faulty fuel injector, listen for any unusual engine noises or misfires. Perform a balance test to identify which injector is causing the problem. Use a diagnostic tool to check for fault codes related to the fuel system. If necessary, remove and inspect the injector for signs of clogging or damage, and replace it if needed.

First, check the oil level and add oil if it's low. Inspect the oil filter for clogs or restrictions, and replace it if necessary. Check the oil pump for wear or damage, and test the oil pressure sensor for accuracy. If these components are functioning correctly, inspect the engine bearings and journals for excessive wear.

Overheating can be caused by several factors. Check the coolant level and refill if necessary. Inspect the radiator for blockages and clean it thoroughly. Verify that the thermostat is functioning correctly and replace it if it's faulty. Check the water pump for leaks or damage, and ensure the cooling fan operates properly. If overheating persists, inspect the cylinder head gasket for leaks.

If the engine has trouble starting, first check the battery charge and connections. Ensure the fuel system is supplying fuel by inspecting the fuel pump and fuel lines for blockages. Check the glow plugs (for diesel engines) or spark plugs (for gasoline engines) for wear and replace them if necessary. Use a diagnostic tool to check for any fault codes that might indicate issues with the engine control unit (ECU) or sensors.

Abnormal exhaust smoke can indicate various engine issues:

1. Black smoke: 

Check for clogged air filters, over-fueling, or issues with the fuel injectors. Inspect the turbocharger (if equipped) for damage.

2. Blue smoke: 

Indicates oil burning. Check for worn piston rings, valve seals, or a damaged turbocharger.

3. White smoke: 

Can be caused by coolant entering the combustion chamber. Inspect the cylinder head gasket, cylinder head, and cooling system for leaks. Additionally, ensure the fuel injectors are operating correctly and not causing unburned fuel to emit as white smoke.

Common faults of hydraulic pumps include insufficient pressure, hydraulic oil leakage, abnormal noise, system overheating and wear of internal pump components.

When the pressure is insufficient, check the hydraulic oil level, filter, hydraulic line leakage, pressure relief valve and internal wear of the pump.

Abnormal noise may be caused by air entering the system, cavitation, internal component wear or hydraulic oil contamination.

Causes of overheating may include low hydraulic oil level, clogged filter, excessive system load or cooling system failure.

Ways to check whether the hydraulic pump is leaking include visually checking whether there is oil around the pump, checking the connections and seals for damage.

Air entering the hydraulic oil will cause unstable system pressure, reduced pump efficiency and abnormal noise.

The way to remove air is to slowly operate all functions of the hydraulic system until the air is exhausted, and check and maintain the hydraulic oil level during this process.

Symptoms of wear include reduced efficiency, increased noise, leakage, and reduced hydraulic function.

The treatment of oil leakage includes replacing seals, repairing or replacing damaged joints or pump housings, and checking and adjusting system pressure.

The way to prevent hydraulic pump failure includes regular maintenance, keeping the hydraulic oil clean, regularly changing filters, and avoiding overload operation.

The steps for replacing the seal are to stop the machine, release the system pressure, remove the pump, replace the seal, reinstall the pump and check the operation.

A control valve failure can cause improper hydraulic function, insensitive operation, hydraulic oil leakage and unstable system pressure.

The pressure relief valve protects the hydraulic system from damage caused by excessive pressure by releasing excess hydraulic oil when the pressure exceeds the set value.

The maintenance frequency of the hydraulic pump is usually performed every 1000 to 2000 hours of operation or once a year according to the manufacturer's recommendations.

The reasons for not working include power supply problems, low hydraulic oil level, filter blockage, hydraulic line leakage and pump internal component failure.

Checking for internal wear requires disassembling the pump and visually inspecting the components, measuring the clearances and comparing to the manufacturer's specifications.

Ways to prevent cavitation include maintaining the proper hydraulic oil level, using the correct oil viscosity, ensuring the filter is clean and avoiding excessive loads on the hydraulic system.

The steps for replacing a control valve are to shut down the machine, release system pressure, remove the old control valve, install the new control valve, start the machine and check operation.

Symptoms of a faulty cooling system include high hydraulic oil temperature, reduced pump efficiency and overheating of the hydraulic system.

Using a hydraulic pressure gauge connected to the pump's test port, operate the excavator to generate pressure and compare the reading to the manufacturer's specifications.

The way to check the filter is to stop the machine, release the system pressure, remove the filter and check for blockage or contamination.

The way to vent after installation is to slowly operate all functions of the hydraulic system until the air is exhausted, and check and maintain the hydraulic oil level during this process.

The way to prevent wear includes regular maintenance, using the right hydraulic oil, keeping the hydraulic system clean, and avoiding overload operation.

The way to deal with overheating is to check the hydraulic oil level, clean or replace the filter, check the cooling system and adjust the system load.

Common causes of control valve failure include internal wear, seal damage, contamination and valve blockage.

The way to check the electrical connection is to visually check whether the connection is loose or damaged, and use a multimeter to test whether the voltage and current are normal.

The way to detect leaks is to visually inspect the hydraulic lines and joints and use a pressure tester to check whether the system pressure is normal.

The reasons for the decrease in efficiency include wear of internal components, filter blockage, hydraulic oil contamination and insufficient system pressure.

Best practices include regular inspection and replacement of hydraulic oil and filters, keeping the system clean, regular inspection and tightening of all connections, and monitoring system pressure and temperature.

The way to test the system after replacement is to start the excavator, slowly operate all hydraulic functions, check system pressure, leakage and operation, and ensure that everything is normal.

Possible low hydraulic oil level, clogged filter, internal wear, or hydraulic line leakage. Solution: Check oil level and refill, clean or replace filter, inspect and repair leaks, check and replace worn parts.

Possible air in the system, cavitation, internal component wear, or oil contamination. Solution: Bleed air from the system, check and fix cavitation sources, replace worn components, replace hydraulic oil.

Possible low hydraulic oil level, clogged filter, excessive load, or cooling system failure. Solution: Check and refill hydraulic oil, clean or replace filter, reduce system load, check and repair cooling system.

Possible loose connections, pipe cracks, or low oil level. Solution: Tighten connections, replace damaged pipes, maintain proper oil level.

Possible internal component wear, clogged filter, oil contamination, or insufficient system pressure.

Solution: Replace worn components, clean or replace filter, replace hydraulic oil, check and adjust system pressure.

Possible low hydraulic oil level, high oil viscosity, or restricted fluid flow.

Solution: Refill hydraulic oil, use correct viscosity oil, check and clear restricted areas.

Possible electrical issues, low hydraulic oil level, clogged filter, or internal pump failure.

Solution: Check electrical connections, refill hydraulic oil, clean or replace filter, inspect and repair or replace pump.

Possible low hydraulic oil, clogged filter, high ambient temperature, or excessive load.

Solution: Refill hydraulic oil, clean or replace filter, ensure good ventilation, reduce system load.

Possible air in the system, clogged filter, or worn pressure relief valve.

Solution: Bleed air from the system, clean or replace filter, replace pressure relief valve.

Possible air in the hydraulic oil or internal component wear.

Solution: Bleed air from the system, replace worn components.

Possible loose installation, unbalanced pump components, or cavitation.

Solution: Tighten installation, balance pump components, check and eliminate cavitation sources.

Possible electrical issues, suction line blockage, or internal pump damage.

Solution: Check electrical connections, clear suction line, inspect and repair or replace pump.

Possible restricted fluid flow, cooling system failure, or high oil viscosity.

Solution: Check and clear restricted areas, check and repair cooling system, use correct viscosity oil.

Possible clogged filter, low hydraulic oil level, or worn pump components.

Solution: Clean or replace filter, refill hydraulic oil, inspect and replace worn components.

Possible inadequate cooling or high oil viscosity.

Solution: Improve ventilation, use correct viscosity oil.

Possible oil contamination, internal wear, or improper maintenance.

Solution: Replace hydraulic oil, replace worn components, perform regular maintenance.

Possible cavitation or debris in the oil.

Solution: Replace damaged impellers, prevent cavitation, filter oil.

Possible loose connections, damaged wiring, or sensor failure.

Solution: Tighten connections, repair wiring, replace faulty sensors.

Regularly changing the engine oil helps maintain the lubrication performance of the engine, prevent wear and extend the service life.

Park the excavator on a flat ground, turn off the engine and wait for a while, then check the hydraulic oil level through the oil level gauge of the hydraulic oil tank.

Usually the hydraulic oil is changed every 2000 hours or as recommended by the manufacturer.

Clean or replace the air filter regularly to ensure the cleanliness and smoothness of the engine intake system.

Regularly checking and replacing the fuel filter can prevent impurities from entering the fuel system, ensure fuel cleanliness and extend the life of the engine.

When the engine is cold, check the coolant level through the level gauge of the coolant tank and add coolant if necessary.

Usually the coolant is changed every two years or as recommended by the manufacturer.

Check the tightness of the track through the tensioner and adjust it if necessary to ensure the normal operation of the track.

Regular lubrication can reduce wear, prevent corrosion, and extend the service life of each component of the excavator.

Regularly check the battery voltage, electrolyte level and connection status to ensure the normal operation of the battery.

Regularly checking and replacing the engine belt can prevent the belt from breaking and ensure the normal operation of the engine.

Check whether there are oil stains on the hydraulic oil tank, oil pipe and joints, and repair them in time if leaks are found.