The maintenance of micro excavators is crucial for ensuring their long-term stable operation and extending their service life. Especially for small equipment such as 1-ton models, which often work under complex conditions (such as courtyards, narrow sites, and dusty environments), more attention should be paid to daily maintenance and regular upkeep. The following details the key points of micro excavator maintenance from three dimensions: daily inspection, regular maintenance, and handling of common faults:
I. Daily Inspection (Must be done before/after each operation)
Daily inspection can promptly identify potential problems and prevent minor faults from expanding. It is recommended to conduct it once before each startup and once after operation, focusing on the following aspects:
1. Appearance and structural components
Check the body for collisions and deformations, especially stress-bearing parts such as the boom, stick, and bucket. If cracks or falling welds are found, stop the machine immediately for maintenance to prevent breakage during operation.
Check the status of tracks/tires: For tracked models, check the tightness of the tracks (when pressing the middle of the track by hand, a sag of about 2-3cm is appropriate) and whether the track plates are loose or broken; for tire models, check the tire pressure, tread wear, and whether there are bulges to avoid slipping or blowouts during driving.
Check whether the connecting pins and bolts are loose, especially the connection between the boom and the body, and between the bucket and the stick. Tighten them in time if looseness is found (operate according to the torque specified in the manual).
Check the status of tracks/tires: For tracked models, check the tightness of the tracks (when pressing the middle of the track by hand, a sag of about 2-3cm is appropriate) and whether the track plates are loose or broken; for tire models, check the tire pressure, tread wear, and whether there are bulges to avoid slipping or blowouts during driving.
Check whether the connecting pins and bolts are loose, especially the connection between the boom and the body, and between the bucket and the stick. Tighten them in time if looseness is found (operate according to the torque specified in the manual).
2. Fluids (oil, water, liquid)
- Fuel: Check the fuel tank level to ensure it is sufficient; observe whether the fuel is turbid (if mixed with water or impurities, it will cause engine wear), and regularly drain the sediment at the bottom of the fuel tank (some models have a drain valve).
- Engine oil: Check the oil level through the dipstick (when the engine is cold, the oil level should be between "MIN" and "MAX"), and observe the color of the oil (normally light yellow; if it turns black or emulsifies, it needs to be replaced in time).
- Hydraulic oil: Check the hydraulic oil tank level (the equipment should be placed on a level ground, with the boom and stick fully retracted when checking). Insufficient oil level will lead to insufficient pressure in the hydraulic system; observe whether the hydraulic oil has bubbles or discoloration (normally light red or light yellow; blackening may indicate oil contamination or overheating).
- Coolant: Check the water tank level. Add the same type of coolant when it is insufficient (do not directly add tap water to avoid scale formation); if the coolant decreases too quickly, check whether the pipelines are leaking.
- Grease (lubricating grease): Inject lubricating grease into the grease nipples of each hinge point (such as boom pins, stick pins, slewing rings, etc.), inject 1-2 times before each operation to ensure sufficient lubrication of moving parts and reduce wear.
3. Core systems
- Engine: Listen for abnormal noises before starting. After starting, observe whether the idle speed is stable and whether there is oil or water leakage. During operation, pay attention to whether the engine speed is normal and avoid long-term overload operation (if the engine fault light appears on the instrument panel, stop the machine immediately for inspection).
- Hydraulic system: When operating various actions (excavating, slewing, walking), feel for jams and abnormal noises, and observe whether the hydraulic pipelines are leaking (if leakage is found, do not touch it with hands, and stop the machine for handling).
- Electrical system: Check whether the instrument panel indicator lights, lights (work lights, turn signals), and horn are normal; check whether the positive and negative wiring of the battery is loose or oxidized (apply vaseline to prevent rust if oxidized).
II. Regular Maintenance (Carry out according to usage time or manual)
The period of regular maintenance needs to be adjusted according to the equipment's usage frequency and working conditions, generally based on "working hours" (such as 50 hours, 100 hours, 500 hours, etc.). The core items include:
| Maintenance period | Main items |
|---|---|
| 50 hours (first time) | Replace engine oil and oil filter; check and tighten all exposed bolts; clean the air filter (blow off dust). |
| 100 hours | Replace the hydraulic oil filter; check the tightness of hydraulic pipelines; clean the air filter again (replace if severely blocked). |
| 200-300 hours | Replace the fuel filter; check the wear of tracks/tires and adjust the tightness of the tracks; inject grease into the slewing ring. |
| 500 hours | Replace hydraulic oil (together with cleaning the hydraulic oil tank); check the engine valve clearance (to be operated by professionals); check the fatigue state of structural parts such as the boom and stick. |
| Long-term storage (e.g., more than 1 month) | Drain all fuel and coolant; remove the battery and store it after charging; lubricate all moving parts; cover the body to prevent dust and rain. |
- Notes on filter replacement: When replacing the oil filter and hydraulic oil filter, drain the old oil first. The new filter should be filled with oil before installation (to avoid dry grinding) and tightened according to the specified torque.
- Oil selection: Strictly use the oil and hydraulic oil of the model specified in the equipment manual (for example, 46# anti-wear hydraulic oil is commonly used for hydraulic oil). Oils of different brands and models must not be mixed to avoid chemical reactions leading to system failures.
III. Common Faults and Simple Handling
Common faults of micro excavators are mostly caused by improper maintenance. The following are minor problems that can be checked by oneself:
- Difficult engine starting:
- Causes: Insufficient fuel, battery power loss, spark plug carbon deposition (gasoline models), clogged fuel filter.
- Handling: Add fuel, start with jumper cables (when the battery is dead), clean or replace the spark plug, replace the fuel filter.
- Slow or weak hydraulic actions:
- Causes: Insufficient hydraulic oil, clogged hydraulic oil filter, insufficient hydraulic pump pressure.
- Handling: Add hydraulic oil, replace the filter; if the pressure is insufficient, professionals are required to inspect the hydraulic pump (possible internal wear or leakage of the pump).
- Walking deviation:
- Causes: Inconsistent tightness of the two sides of the tracks (tracked models), uneven oil quantity in the travel motors, unequal tire pressure (tire models).
- Handling: Adjust the tightness of the tracks, check the travel motor pipelines; replenish the tire pressure to the standard value.
- Engine overheating:
- Causes: Insufficient coolant, clogged water tank radiator (covered by weeds and dust), loose fan belt.
- Handling: Add coolant, clean the radiator (wash with a high-pressure water gun), adjust the tightness of the belt.
IV. Maintenance Notes
- Safety first: Stop and turn off the engine during maintenance, and pull the handbrake. When checking the hydraulic system, lower the boom and stick to the ground and release the system pressure to avoid oil spraying and hurting people.
- Record maintenance logs: Record the time, items, and models of replaced parts for each maintenance to facilitate tracing the equipment status and planning the next maintenance in advance.
- Do not be arrogant about professional issues: For engine internal maintenance, hydraulic pump disassembly, complex faults of the electrical system, etc., contact the brand after-sales service or professional maintenance personnel to avoid secondary damage caused by improper operation.
Through standardized daily inspections and regular maintenance, the service life of 1-ton micro excavators can be extended to 5-8 years (depending on the frequency of use and working conditions). At the same time, it can reduce the downtime due to faults and lower the long-term use cost.
