Remanufactured fuel injection pump, cross-ref 4063844. Bench-tested before shipment.
Quote within 24 hours. Send a photo of your nameplate and we will confirm the exact match.
4063844 is supplied as a remanufactured replacement fuel injection pump. Cross-reference numbers: 4063844. Application recorded for this part: Fits Cummins — 6BT5.9. This pump has two jobs that are easy to conflate: raising fuel to injection pressure, and metering the correct quantity at the correct moment. Wear affects both. The result is usually a combination of harder starting, drifting timing and visible smoke rather than one clean fault. Expect extended cranking especially when hot, hesitant throttle response, smoke that persists rather than clears, timing that drifts or will not hold, and in some cases fuel in the sump or a pump body running unusually hot. Before condemning the pump, rule out the cheap causes: supply restrictions, a weak lift pump, air ingress on the suction side and a blocked filter. Check supply pressure and condition at the pump inlet first, then look at delivery and timing. Set timing to the engine’s marks and never lever the pump into place — bar the engine over instead. Prime thoroughly, use a new mounting seal, verify lift pump supply pressure, and bleed before starting. A dry start is the fastest way to ruin a sound pump. Rebuilt rather than refurbished: full teardown and measurement, worn components replaced instead of cleaned and reused, sealing surfaces restored to specification, then bench calibration and testing. The record is what separates this from a used part — we can provide the test sheet for your order. Covered by a 12-month warranty.
| Part number | 4063844 |
| Condition | Remanufactured (not a genuine OEM new part) |
| Application | Fits Cummins — 6BT5.9 |
| 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 |
Three very different things are sold under similar descriptions. Here is what separates them, and what to ask before you buy.
Read the guide →The pump sets pressure, quantity and timing. Here is how wear shows up, and the checks that separate pump faults from supply faults.
Read the guide →Water, dirt and misfuelling damage common rail components differently. What to check, and why cleaning the system matters as much as replacing parts.
Read the guide →
