original 0R-3421 Fuel Injector Nozzle 0R3421 4W-7017 4W7017 OR-1744 Diesel Injector Pump for 3306 3406 3406B 3408 3412 Excavator 245 Parts original new injector

Engineered as a direct-fit replacement within heavy-duty diesel fuel systems, the 0R-3421 Fuel Injection Nozzle Assembly delivers precision-controlled fuel atomization for 3406B, 3406C, 3408B, and 3408C engine platforms. Remanufactured to OEM-equivalent specifications, this nozzle assembly supersedes legacy part number 4W-7017 and cross-references to M-0R3421, ensuring seamless interchangeability across original and aftermarket service programs. It is qualified for use in construction, mining, marine, oil & gas, agricultural, and power generation applications.

The 0R-3421 nozzle features high-precision needle valve geometry and calibrated spray orifices designed to promote optimum combustion efficiency, reduced soot formation, and lower fuel consumption. Field-proven benefits include improved cold-start performance, reduced engine deposits, smoother idle, sharper throttle response, and extended injector service life. Compatible equipment includes the 245B and 245D excavators, 980C and 980F wheel loaders, 621E, 621F, 623E, 627E, and 627F scrapers, 824C and 825C machines, 16G motor graders, 773B off-highway trucks, and SR4 generator sets.

For maximum reliability, operators should use ISO-compliant diesel fuel, replace filters on schedule, and monitor injector balance rates and exhaust smoke conditions. Installation requires cleaning the injector seat, verifying the nozzle part number, replacing sealing components, applying OEM torque specification, and bleeding the fuel system. Diagnostic guidance addresses hard start, black smoke, elevated fuel consumption, power loss, and rough idle conditions to safeguard uptime in severe-duty environments.