original 258-8745 C9 Diesel Engine Fuel Injector 10R7221 Replacement for OEM Construction Machinery Spare Parts new injector original new original new injector

Engineered specifically for the C9 diesel platform, the 258-8745 fuel injector delivers precise atomization and consistent high-pressure delivery through advanced common rail technology. Its hardened steel alloy construction withstands extreme combustion pressures and repeated thermal cycling, while the multi-hole nozzle geometry produces optimized spray patterns that improve fuel economy and reduce particulate emissions. Built to meet and exceed OEM performance standards, this injector provides exact fitment, accurate timing, and reliable operation across every C9 configuration, including the C9 ACERT variant with advanced combustion control and industrial C9 units used in stationary generator sets.

The injector is a direct-match replacement for the authorized part 258-8745 and is fully cross-referenced with 2588745, CA2588745, 254-4339, 254-4340, 265-8106, 266-4446, 267-3360, 267-3361, 267-9710, 267-9717, and 267-9722, offering broad compatibility for fleet operators, service shops, and equipment rental providers. It integrates seamlessly with global common rail systems and is suitable for excavators such as the 330D, 336D, and 340D, wheel loaders including the 966H and 972H, as well as industrial generators, mining machinery, marine auxiliary engines, and backup power units that rely on the C9 engine.

Routine maintenance is essential for long-term injector reliability. Operators should always use high-quality diesel fuel with proper cetane rating, avoid contaminated or low-cetane supplies, and protect the system from moisture intrusion. Approved diesel injector cleaners are recommended during scheduled service, and ultrasonic cleaning is advised for severe deposit accumulation. Common failure indicators include worn nozzles, electrical control malfunctions, leaking injector seals, and injector drift, which can be accurately diagnosed using a flow bench, pressure sensors, ECU fault code readers, and ultrasonic cleaning test rigs to restore original engine performance.