The 0 445 025 604 high‑pressure common rail fuel injection pump (Bosch number 0445025604) is a precision‑engineered component fully compatible with Bosch CP3 or CP4 architecture. It is specifically calibrated for the CB28S2 / MM3 diesel engine family – a rugged 4‑cylinder, 2.8L to 3.0L industrial engine widely used in agricultural tractors, compact loaders, forklifts, and small gensets.
This pump delivers stable rail pressure up to 1,800 bar, ensuring efficient combustion, low emissions, and reliable cold starts even in harsh off‑highway conditions. Rsolid Engine Parts supplies the 0 445 025 604 as a brand‑new, Bosch‑compatible unit – 100% calibration tested, and backed by a full 12‑month warranty at competitive pricing.
1. Structural Advantages of the Bosch 0 445 025 604 Pump
The 0 445 025 604 is a high‑pressure common rail pump, typically based on the Bosch CP3 (three‑plunger) or CP4 (two‑plunger) platform. Its design offers several key benefits for CB28S2 / MM3 industrial engines:
Radial Piston Design (3 or 2 plungers) – Depending on the variant, the pump uses either three (CP3) or two (CP4) plungers arranged radially around an eccentric cam. This delivers exceptionally smooth, high‑volume fuel flow with minimal pressure pulsation, reducing stress on the common rail and injectors.
Integrated Vane‑Type Transfer Pump – A built‑in low‑pressure vane pump draws fuel directly from the tank and supplies the high‑pressure section, ensuring consistent inlet pressure even when the vehicle’s lift pump is weak – ideal for ageing equipment.
High‑Pressure Capability (Up to 1,800 bar) – The pump generates rail pressures up to 1,800 bar (26,100 psi), enabling superior fuel atomisation for complete combustion, lower soot formation, and improved fuel economy.
Heavy‑Duty Drive Shaft & Bearings – Designed to withstand the torsional loads and vibration of 4‑cylinder industrial diesels, ensuring long service life in construction, agricultural, and material‑handling applications.
High‑Pressure Fuel Lubrication – All moving internal parts (plungers, roller shoes, eccentric cam) are lubricated solely by diesel fuel, eliminating external oil lines and simplifying installation.
Integrated Flow Control Valve (ZME) – An inlet metering solenoid valve precisely regulates fuel entry based on ECU demand, providing accurate rail pressure control, improved throttle response, and lower fuel consumption.
Robust Cast Housing with Anti‑Corrosion Coating – The pump body is manufactured from high‑strength materials with a protective coating, engineered to withstand the vibration, thermal cycling, dust, and moisture typical of off‑highway environments.
Direct Bosch Compatibility – Identical mounting flange (SAE standard), drive gear interface, high‑pressure outlet ports, and electrical connector as the original Bosch 0 445 025 604. True plug‑and‑play replacement with no modifications.
2. Compatible Engine & Equipment Models (≤5)
The 0 445 025 604 pump is specifically calibrated for the CB28S2 / MM3 diesel engine – a 4‑cylinder, 2.8L to 3.0L common rail industrial engine. This engine is found in a variety of equipment from manufacturers such as Kohler, Lombardini, Kubota (some models), or Chinese brands (Weichai, Yuchai, etc.). Typical applications include:
Agricultural tractors – Small to medium tractors (30–60 HP) fitted with CB28S2 / MM3 engines (e.g., certain models from Farmtrac, Solis, or Zetor).
Compact wheel loaders – Loaders from manufacturers like SDLG, XCMG, or Liugong using the MM3 engine.
Forklifts – Counterbalance forklifts (2.5–3.5 tonne capacity) with CB28S2 diesel engine (e.g., some Heli, Hangcha, or Toyota industrial variants).
Skid steer loaders / compact track loaders – Units from Sunward, Bobcat (with certain Deutz or other power) that specify the CB28S2.
Generator sets – Small industrial gensets (15–40 kVA) powered by the MM3 common rail engine.
✅ Important Fitment Note – Always verify your original pump Bosch number (0 445 025 604) and your engine model (CB28S2 / MM3). The pump is often stamped with the 10‑digit Bosch number. If your engine has a different pump number, consult us before ordering.
3. Common Failures & Professional Installation/Replacement Advice
3.1 Typical Symptoms of a Failing 0 445 025 604 Pump
Loss of power under load – The equipment struggles to lift, dig, or pull, often accompanied by black exhaust smoke.
Extended cranking time before start – The engine takes longer than normal to start, especially after overnight parking.
Engine surging or rough idle – Inconsistent fuel delivery at low RPM, causing the engine to hunt or misfire.
DTC codes P0087, P0088, or P0191 – Rail pressure too low, too high, or fuel pressure sensor rationality.
Metal particles in the fuel filter – A clear sign of CP3/CP4 internal wear (plunger scuffing or roller bearing failure). Even small ferrous particles indicate imminent pump failure.
External fuel leakage – Visible diesel wetness around the pump body, particularly at the drive shaft seal or around the ZME metering valve.
Diesel contamination in engine oil – A failed drive shaft seal allows fuel to enter the timing case and then the engine oil sump. Check for rising oil level and a diesel smell.
3.2 Professional Installation & Replacement Recommendations
Perform a complete fuel system diagnosis – Before pump replacement, use a compatible diagnostic tool (e.g., Bosch KTS, generic scanner with live data) to verify rail pressure values, injector return flow rates, and identify any related faults.
Replace the fuel metering valve (ZME) – If the old pump has failed, it is strongly recommended to replace the ZME solenoid valve with a new one at the same time. A faulty ZME can cause repeat pump failure.
Replace all fuel filters – Install new primary (water separator) and secondary fuel filters before running the new pump. The CP3/CP4 pump is highly sensitive to contamination.
Flush the entire fuel system – Drain and clean the fuel tank. Blow out all supply and return lines with compressed air. Replace any rubber hoses that show degradation. This step is non‑negotiable – debris from a failed pump will destroy a new unit within minutes.
Inspect and flow‑test all injectors – Worn or stuck injectors with high return flow will prevent the pump from building correct rail pressure and will cause repeat pump failure. Have all injectors professionally tested and cleaned or replaced as necessary.
Replace the engine oil and filter – If diesel has contaminated the oil (rising level or diesel smell), change the oil and filter BEFORE running the new pump.
Prime the low‑pressure circuit – Use a hand vacuum pump on the fuel return line to pull bubble‑free fuel through the pump and filters. Never dry‑crank the pump – CP3/CP4 pumps are sensitive to aeration.
Fill the pump with clean diesel – Remove the high‑pressure outlet fitting and pour clean, lubricious diesel (or Bosch special assembly lubricant) into the pump housing to prevent dry start scoring of the plungers and eccentric cam.
Torque all connections to specification – High‑pressure outlet (M14×1.5 cone seal): 35–45 Nm. Low‑pressure inlet (M16×1.5): 25 Nm. High‑pressure line union nuts: 35–40 Nm. Drive shaft nut: consult the equipment workshop manual (typically 80–120 Nm). Use a calibrated torque wrench.
Reset fuel adaptations – After installation, use a diagnostic tool to clear learned fuel trim values and perform a “high‑pressure pump adaptation” or “fuel system learn” routine.
Perform a leak test – Idle the engine for 10 minutes, then inspect all high‑pressure and low‑pressure unions, the pump mounting area, and the drive shaft seal for any signs of fuel wetness. Pay special attention to the high‑pressure line connections.
Monitor rail pressure – Using live data on your diagnostic tool, verify that actual rail pressure tracks within ±20 bar of specified value across all RPM ranges.
💡 Pro Tip – The CB28S2 / MM3 engine is often used in dusty, wet, or high‑humidity environments. Always drain the water separator daily. Consider installing an additional 5‑micron secondary fuel filter to extend pump and injector life. Use high‑quality diesel with proper lubricity, especially when running biodiesel blends.
4. Why Choose Rsolid Engine Parts as Your Supplier
✅ Exact Bosch Compatibility – Direct replacement for 0 445 025 604 on CB28S2 / MM3 engines and related industrial equipment. No modifications required.
✅ 100% Calibration Tested – Each pump is run on a Bosch EPS 200 or equivalent test bench to verify delivery volume, rail pressure stability, ZME regulator response, and leak‑free operation. Test reports available.
✅ 12‑Month Warranty – Full coverage against manufacturing defects for all pumps supplied, even for off‑highway and industrial applications.
✅ Competitive Pricing for Workshops & Dealers – Volume discounts available for repair shops, equipment dealers, rental fleets, and parts distributors.
✅ Fast Worldwide Shipping – Stock held in multiple warehouses for rapid dispatch to Europe, Asia, Africa, the Americas, and the Middle East.
✅ Expert Technical Support – Our diesel injection specialists provide pre‑purchase fitment verification, diagnostic assistance, and detailed installation guidance via WhatsApp or email.
Contact Rsolid Engine Parts Today
📞 WhatsApp: +8615975376778
📧 Email: amy@rinjector.com
