
Frequently questions
1.OEM Parts: Manufactured by the excavator’s original equipment manufacturer (e.g., Caterpillar, Komatsu, Sany) or authorized by them. These carry the OEM’s logo and packaging. Advantages include superior quality, 100% dimensional accuracy, most stable performance, and coverage under the original manufacturer’s warranty.
2.Branded Parts (also known as High-Quality Compatible Parts): Manufactured by internationally or domestically renowned specialized component manufacturers (e.g., Bosch in Germany, NKC in Japan). These manufacturers may themselves be suppliers to the original equipment manufacturers. Advantages include quality comparable to OEM parts, more affordable pricing, and high cost-effectiveness.
3. Aftermarket Parts (also known as compatible or imitation parts): Produced by non-authorized manufacturers. Advantages include extremely low prices.
1.Inspect the packaging: Genuine and branded parts feature clear printing on sturdy packaging, with distinct brand logos, part numbers, production dates, and anti-counterfeiting labels.
2. Verify markings: Scan the anti-counterfeiting code or QR code on the packaging to check authenticity on the official website or WeChat account. Examine the part itself for clear, standardized stamping or labels.
1.Most reliable: Consult the included Parts Manual or use the OEM’s official Electronic Parts Catalog (EPC) system.
2.Provide details: Give your excavator’s exact model (e.g., CAT 320D) and serial number/chassis number (crucial! Parts from different batches of the same model may vary) to the supplier.
1.Pilot system: Insufficient pilot pressure (check pilot pump, pilot filter).
2.Main hydraulic system: Insufficient output pressure from the main pump, stuck or internal leakage in the main control valve spool, or malfunctioning main relief valve.
3.Actuators: Severe internal leakage in hydraulic cylinders or motors.
4.Control aspects: Sensor failure or electrical circuit issues (for modern electronically controlled excavators).
Frequently questions
1.There’s no fixed answer; it depends on the operating environment and hours worked.
2.By time/hours: Follow the recommendations in the operation manual (typically 250-500 hours).
1. Oil compatibility: Use only the grade and type of hydraulic oil specified in the manual. Do not mix different brands or grades.
2. Maintain cleanliness: Perform the change in a dust-free environment. Ensure all tools (oil drums, funnels, etc.) are absolutely clean to prevent contaminants from entering the system.
3. Simultaneous Replacement: When changing hydraulic oil, the return oil filter and pilot filter must be replaced simultaneously.
4. Air Bleeding: After replacement, start the engine and slowly operate each function to bleed air from the hydraulic system. Then check the oil level and top up to the standard mark.
1.Replacement criteria: Replace bucket teeth when worn to one-third of their original thickness or severely deformed, and replace cutting edges when wear affects the digging angle.
2.Replacement Tips: Replace in sets to maintain balance and efficiency. Use dedicated pins and hammers during replacement, prioritizing safety. Applying a small amount of grease to pins facilitates installation and future removal.
1.Hydraulic oil: Low oil level, degraded oil quality, incorrect oil grade.
2.Cooling system: External clogging of the hydraulic oil cooler by dust/debris, or internal blockage; loose or damaged cooling fan belt.
3.Hydraulic system: Clogged return oil filter; main relief valve set too high or stuck open; severe internal leakage in the hydraulic pump.
1.Worn piston rings/cylinder liners: The most common cause, allowing oil to enter the combustion chamber.
2.Valve stem seal deterioration: Oil seeps into combustion chamber through valve guides.
3.Turbocharger oil leak: Damaged turbine-end seal allows oil into intake duct.
4.External leakage: Inspect gaskets on oil pan, valve cover, etc., for aging or seepage.

