Maintenance and repair of excavators
The purpose of implementing regular maintenance and upkeep for excavators is to reduce machine failures and extend the service life of the machine; Shorten the downtime of the machine; Improve work efficiency and reduce operating costs. As long as fuel, lubricating oil, water, and air are well managed, 70% of failures can be reduced. In fact, about 70% of failures are caused by poor management.

1. Fuel management
Different grades of diesel should be selected according to different environmental temperatures; Diesel fuel should not be mixed with impurities, dust, and water, otherwise it will cause premature wear of the fuel pump; The high content of paraffin and sulfur in inferior fuel can cause damage to the engine; After completing daily operations, the fuel tank should be filled with fuel to prevent water droplets from forming on the inner wall of the fuel tank; Open the drain valve at the bottom of the fuel tank to drain water before daily operations; After the engine runs out of fuel or the filter element is replaced, the air in the pipeline must be drained.

2. Management of Other Oils
Other oils include engine oil, hydraulic oil, Gear oil, etc; Different grades and grades of oils cannot be mixed; Different types of excavator oils have different chemical or physical additives added during the production process; Ensure that the oil is clean and prevent impurities (water, dust, particles, etc.) from entering; Select the oil grade based on environmental temperature and usage. When the ambient temperature is high, oil with high viscosity should be used, and when the ambient temperature is low, oil with low viscosity should be used; The viscosity of Gear oil is relatively large to adapt to larger transmission loads, and the viscosity of hydraulic oil is relatively small to reduce fluid flow resistance.

3. Lubricating grease management
The use of lubricating oil (butter) can reduce wear on moving surfaces and prevent noise. When storing and storing lubricating grease, dust, sand, water, and other impurities should not be mixed in; It is recommended to use lithium based grease G2-L1, which has good wear resistance and is suitable for heavy-duty working conditions; When filling, try to squeeze out all the old oil and wipe it clean to prevent sand from sticking.

4. Maintenance of filter element
The filter element plays a role in filtering impurities in the oil or gas circuit, preventing them from invading the system and causing malfunctions; Various filter elements should be replaced regularly according to the requirements of the operation and maintenance manual; When replacing the filter element, it is necessary to check whether there are metal particles attached to the old filter element. If any metal particles are found, timely diagnosis and improvement measures should be taken; Use pure filter elements that comply with machine regulations. The filtering ability of fake and inferior filter elements is poor, and the quality of the filter layer and materials does not meet the requirements, which will seriously affect the normal use of the machine.

5. Content of regular maintenance
① After the new machine has been operating for 250h, the fuel filter and additional fuel filter should be replaced; Check the clearance of the engine valves.
② Daily maintenance; Check, clean or replace the air filter element; Clean the interior of the cooling system; Check and tighten the track shoe bolts; Check and adjust the reverse tension of the track; Check the intake heater; Replace the bucket teeth; Adjust the bucket clearance; Check the front window cleaning fluid level; Check and adjust the air conditioning; Clean the floor inside the driver's cab; Replace the crusher filter element (optional). When cleaning the inside of the cooling system, wait for the engine to fully cool down, slowly loosen the water filling cap, release the internal pressure of the water tank, and then drain the water; Do not carry out cleaning work while the engine is working, as high-speed rotating fans can cause danger; When cleaning or replacing the coolant, the machine should be parked on a level surface.
③ Inspection items before starting the engine. Check the level and height of the coolant (add water); Check the engine oil level and add oil; Check the fuel level (refueling); Check the hydraulic oil level (add hydraulic oil); Check if the air filter is blocked; Check the wires; Check whether the horn is normal; Check the lubrication of the bucket; Check for water and sediment in the oil-water separator.
④ Every 100 maintenance items. Boom cylinder head pin shaft; Boom foot pin; Boom cylinder rod end; Stick cylinder head pin shaft; Boom and stick connection pins; Stick cylinder rod end; Bucket cylinder head pin shaft; Half rod connecting rod connecting pin; Stick, bucket cylinder rod end; Bucket cylinder head pin shaft; Stick connecting rod connecting pin; Check the oil level inside the rotating mechanism box (add oil); Drain water and sediment from the fuel tank.
⑤ Maintenance items every 250H. Check the oil level in the final drive box (add Gear oil); Check the battery electrolyte; Replace the oil in the engine oil pan and replace the engine filter element; Lubricating the slewing bearing (2 places); Check the tension of the fan belt and adjust the tension of the air conditioning compressor belt.
⑥ Maintenance items every 500 hours. Simultaneously carry out maintenance projects every 100 and 250 hours; Replace the fuel filter element; Check the height of the lubricating grease on the rotating pinion (add lubricating grease); Check and clean the radiator fins, oil cooler fins, and cooler fins; Replace the hydraulic oil filter element; Replace the oil in the final drive box (only at 500h for the first time, once every 1000h thereafter); Clean the air filter elements inside and outside the air conditioning system; Replace the hydraulic oil vent filter element.
⑦ Maintenance items every 1000 hours. Simultaneously carry out maintenance projects every 100, 250, and 500 hours; Replace the oil in the rotating mechanism box; Check the oil level of the shock absorber housing (return oil); Check all fasteners of the turbocharger; Check the clearance of the turbocharger rotor; Check and replace the tension of the generator belt; Replace the anti-corrosion filter element; Replace the oil in the final drive box.
⑧ Maintenance items every 2000 hours. Complete maintenance items every 100, 250, 500, and 1000 hours first; Clean the hydraulic oil tank filter screen; Clean and inspect the turbocharger; Check the generator and starting motor; Check the engine valve clearance (and adjust it); Check the shock absorber.
⑨ Maintenance over 4000 hours. Increase the inspection of water pumps every 4000 hours; Increase the project of replacing hydraulic oil every 5000h.
⑩ Long term storage. When the machine is stored for a long time, in order to prevent rust on the piston rod of the hydraulic cylinder, the working device should be placed on the ground; Wash and dry the entire machine and store it indoors in a dry environment; When limited by conditions and can only be stored outdoors, the machine should be parked on a well drained cement floor; Before storage, top up the fuel tank, lubricate all parts, replace hydraulic oil and engine oil, apply a thin layer of grease to the exposed metal surface of the hydraulic cylinder piston rod, remove the negative terminal of the battery, or remove the battery for separate storage; Add an appropriate proportion of antifreeze to the cooling water according to the minimum ambient temperature; Start the engine once a month and operate the machine to lubricate various moving parts while charging the battery; Turn on the air conditioner for 5-10 minutes of cooling operation.