0445120251 Common Rail Diesel Injector – Bosch OEM CRIN For 6.7L Platform

This Bosch common rail injector 0445120251 (OEM cross-reference 5263314) serves as a direct-fit replacement for 6.7L diesel platforms deployed across industrial, marine, and construction applications. The unit operates within high-pressure common rail fuel systems where injection timing and fuel quantity are managed electronically by the ECM rather than mechanically. For repair shops maintaining Komatsu excavators or heavy equipment, this injector restores combustion efficiency, reduces exhaust smoke, and eliminates misfire codes associated with worn nozzle assemblies.

The table above consolidates fitment data that wholesale buyers and diesel parts distributors request most frequently during procurement. The 5263314 interchange appears on equipment parts catalogs, while the 0445120251 designation remains the Bosch factory reference used by authorized service centers and independent repair garages.

Beyond the primary 6.7L CRIN application, this injector cross-references into Komatsu 4D107 and 6D107 power plants, making it a stock-keeping priority for shops servicing PC200-8 and PC220-8 hydraulic excavators. 5.9L common rail installations also accept this unit, particularly in power generation and marine propulsion configurations where constant-load duty cycles accelerate internal seat wear. Agricultural equipment and material handling fleets running the 6.7-liter common rail platform share the same injector bore geometry, so a single SKU covers multiple service verticals without inventory duplication.

Before removal, fuel rail pressure must be released and the high-pressure lines capped to prevent contaminant ingress. The copper combustion seal and O-ring at the nozzle body must be replaced unconditionally-reusing them risks compression leakage and carbon tracking along the injector shaft. Tightening torque follows the OEM sequence: stage one at 8 Nm, final torque at 30 Nm on the hold-down clamp. Lubricate the injector body O-rings with clean diesel fuel or silicone grease before seating. After installation, run a bubble test on the return line and verify rail pressure stabilizes within ECM-specified limits. Skipping the fuel filter replacement during injector service is a leading cause of premature repeat failure-the QR code on the injector body confirms authentic Bosch calibration.

Q1: Will this injector require ECM coding after installation?
A: Yes. Bosch CRIN injectors carry an IMA code (injector quantity adjustment) etched on the body. The ECM must be updated with this code to maintain injection duration accuracy and avoid rough idle or excess fuel delivery.

Q2: What distinguishes this from remanufactured or "rebuilt" units?
A: This is a brand-new, boxed Bosch unit-not a reman core with exchanged internals. New units deliver factory-matched nozzle and actuator pairs, which reman processes cannot fully replicate for long-term injector balance.

Q3: Are there counterfeit versions circulating in the aftermarket?
A: Yes, particularly for 5263314 cross-references. Counterfeit units often use inferior solenoid materials that degrade under 1,600 bar rail pressure. Verify the Bosch holographic label and production date code on the packaging.

Q4: What causes repeat injector failure on 6.7L engines?
A: Fuel contamination remains the leading factor. Water ingress or particulate matter passing through a degraded filter erodes the control valve seat. Always flush the rail and lines during replacement.

Q5: Is this injector suitable for marine 6.7L applications?
A: Yes, provided the fuel return system is correctly routed and the ECM calibration matches the marine power rating. Marine duty cycles require stricter fuel filtration-10-micron absolute minimum.

Q6: What is the standard warranty term for this unit?
A: Twelve months from invoice date against manufacturing defects. Warranty exclusions apply to fuel contamination damage, improper installation torque, and electrical connector corrosion.