4719921 Original Excavator Fuel Filter for Hitachi ZX450-3

Part number 4719921 is the original fuel filter (diesel filter element) provided by Hitachi Construction Machinery for the ZX450-3 series 45 ton large hydraulic excavator. This component is mainly used for fuel system filtration, effectively intercepting pollutants such as moisture, impurities, and gum in diesel, ensuring clean fuel supply to the engine and normal operation of fuel injectors. Its universal models cover three series of large excavators including Hitachi ZX450-3, ZX470-3, ZX420-3, as well as some equivalent platform models such as ZAXIS450-3 and ZAXIS470-3. As a core maintenance component of the original factory, its interface size and sealing performance are precisely matched with the engine fuel pipeline. The use of non-standard auxiliary components is strictly prohibited to avoid fuel system blockage, injector wear, or engine power reduction.

This product is a rotary fuel filter. The outer shell material is usually cold-rolled steel plate+anti-corrosion coating, and the interior is made of multi-layer composite filter paper (cellulose+glass fiber+waterproof layer). Typical technical parameters: filtration accuracy of 5-10 microns, initial filtration efficiency ≥ 99.5%, working pressure of 0.4-0.6MPa, burst pressure ≥ 2.0MPa, working temperature -30 ℃ to+100 ℃. The filter is equipped with an oil-water separator (with a transparent water storage cup) and a manual pump for regular drainage. The sealing ring is made of fluororubber, which is resistant to diesel and high temperatures, ensuring 100% sealing without oil leakage.

Replacement cycle: every 500 working hours or every 6 months (whichever comes first); If the fuel quality is poor (high sulfur content, high impurities), it is recommended to shorten it to 250 working hours. Replacement steps: 1 Turn off the engine and wait for 5 minutes to release the fuel system pressure; 2. Place an oil pan under the filter; 3. Use a specialized filter wrench to loosen the old filter counterclockwise (pay attention to residual diesel); 4. Clean the sealing surface of the filter seat; 5. Apply clean diesel evenly on the sealing ring of the new filter; 6. Tighten clockwise by hand until the sealing ring contacts the base, then use a wrench to tighten 3/4 turn (torque 15-20N · m). Attention: 1 Before replacing the filter, the air in the fuel system must be drained (using a manual pump); 2. Before installation, check whether the filter housing is bumped or deformed; 3. After replacement, start the engine and run it at idle for 5-10 minutes to check for oil leakage and whether the engine runs smoothly; 4. Regularly (every 50 working hours) check the water storage cup of the oil-water separator and drain it in a timely manner; 5. Discarded filters should be disposed of according to environmental regulations (strictly prohibited from being discarded at will). Always use genuine original parts and operate according to the maintenance manual to ensure long-term stable operation of the fuel system.