Remanufactured fuel injection part, cross-ref 4903475, 4307525, QSN14. Bench-tested before shipment.
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4903475 is supplied as a remanufactured replacement fuel injection part. Cross-reference numbers: 4903475, 4307525, QSN14. Application recorded for this part: Fits Cummins — N14. An injector is a high-speed valve. It has to hold back rail pressure, then open and close within a fraction of a crankshaft degree — several times per cycle on pilot-injection engines. Anything that alters opening behaviour, whether it is carbon on the tip, a worn needle or a tired solenoid, changes how the cylinder burns its charge. Typical signs are poor starting hot or cold depending on whether the unit is weeping or sticking, an idle that hunts or sounds uneven, smoke under acceleration, and sometimes a smell of diesel in the oil where an injector is leaking internally. A back-leakage comparison across the set is the cheapest meaningful test: uneven return between cylinders points at the failing unit. Follow it with a cut-out test to confirm which cylinder actually stops contributing. Installation notes: new copper washers and seals are mandatory, the seat must be clean and undamaged, and the retainers should be torqued to the engine manufacturer's specification. If the ECU stores injector codes for this engine, program them after fitting, otherwise the engine will not compensate correctly. Rebuild process: full teardown and measurement first, then replacement of all wear components, machining back to specification where required, followed by calibration and bench testing. The difference between this and a cleaned used part is the measurement and test record — we hold every unit to the specification for the part number, not just to 'it runs'. Test sheets available on request, and every unit ships with a 12-month warranty.
| Part number | 4903475 |
| Condition | Remanufactured (not a genuine OEM new part) |
| Cross-reference | 4903475, 4307525, QSN14 |
| Application | Fits Cummins — N14 |
| Process | Disassembled, cleaned, measured, wear parts replaced, machined to specification |
| Bench test | Delivery, return flow, opening pressure and leakage recorded before dispatch |
| Warranty | 12 months |
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