HP4 Diesel Fuel Injector Pump 294050-0039 22100-E0253 for Hino J08e Engine Fuel Pump Assy

This high-pressure diesel common-rail fuel pump assembly (Part ID: 294050-0039 / 2940500039; common OE cross-references include 22100-E0020, 22100-E0021, 22100-E0022, 22730-1050, etc.) is precision-engineered. Designed for the J08E / J08E-TM / J08E-UR series 7.7L six-cylinder diesel platform, it is widely used in 500-series heavy-duty trucks, large passenger buses, and various construction machinery. As the core component responsible for generating ultra-high rail pressure and ensuring stable fuel delivery, it efficiently pressurizes low-pressure diesel and distributes it evenly to the high-pressure fuel rail, guaranteeing a continuous and steady fuel supply across all engine speeds and operating conditions.

The pump body is constructed from high-strength forged alloy, while the core plunger and control valve spool undergo precision quenching and are treated with ultra-hard, wear-resistant coatings to effectively resist impurity erosion and internal pressure loss. Upon installation, operators and technicians will notice a significant improvement in power delivery: cold starts are quick and smooth, idle operation is stable, and pump noise is reduced. During heavy-load hill climbing or long-distance highway cruising, throttle responsiveness is markedly enhanced, providing agile and robust power that restores factory-level driving quality and excellent fuel efficiency.

Direct-from-factory manufacturing with optimized cost management throughout the process. We provide a one-stop, high-standard parts supply solution that eliminates the hassles of complex procurement, excessive intermediary markups, and inconsistent quality tolerances. Leveraging standardized, precision assembly lines, we ensure highly consistent fuel pressure and flow control across all cylinders, delivering reliable power output for vehicles and equipment while keeping maintenance budgets under control.

Dynamic pressure testing across all operating conditions and rigorous quality inspections. Designed to address issues such as oil pressure fluctuations, sluggish acceleration, and intermittent warning lights often caused by substandard components. Before leaving the factory, every high-pressure pump undergoes automated bench testing that simulates real-world high-temperature and high-pressure conditions. Precision testing of sealing integrity and fuel return rates across various pressure ranges ensures the unit is ready for immediate installation, significantly reducing the time and cost associated with assembly and adjustment.

Large-scale, consistent inventory and rapid shipping capabilities. Aimed at minimizing downtime losses and operational delays for commercial vehicles and heavy equipment caused by fuel system failures. Our warehouse maintains ample stock of core specifications; orders are quickly processed and shipped within 24–48 hours, effectively shortening wait times and helping fleets and vehicle owners get back to work quickly.

High-hardness, corrosion-resistant valve components with wear-resistant coatings. Engineered to combat premature component wear and valve spool sticking caused by poor diesel lubricity or high sulfur content in certain regions. Critical internal wear parts are crafted from premium special-alloy bearing steel and treated with specialized surface hardening processes; this ensures exceptional fatigue and wear resistance, maintaining stable performance under harsh conditions and prolonged continuous operation, thereby significantly extending service life.

Heavy-duty truck trunk-line logistics and long-haul freight: Heavy-duty trucks equipped with 7.7L diesel engines operate under full load for extended periods on major highways. When vehicles experience power struggles while climbing in high gears, sluggish acceleration, or abnormal fuel consumption, maintenance teams install this high-pressure fuel supply pump. Post-installation, fuel pressure builds rapidly and remains stable; acceleration under heavy loads becomes robust and responsive, ensuring long-haul transport tasks are completed efficiently and on schedule. Intercity and Commuter Bus Operations: Large passenger buses endure long-distance daily travel, demanding exceptional engine stability and consistent fuel delivery. When vehicles exhibit sluggish cold starts, noticeable low-speed vibration, or intermittent low-oil-pressure warnings, technicians can promptly install this high-specification high-pressure fuel pump to restore power output and smooth operation, ensuring a comfortable and safe journey.

Q: Can the fuel pump be installed and used immediately upon receipt? Is recalibration required?

A: Pressure and flow rate calibrations across all operating conditions are completed prior to shipment. Provided the fuel lines are clean, the unit can be put into service immediately after installation by a professional technician using standard torque specifications and proper air-purging procedures.

Q: What are the lead times and stock availability for bulk orders?

A: We operate our own production facilities and warehousing centers, maintaining a steady stock of this model year-round. Standard orders ship within 24–48 hours of confirmation, while bulk orders can be quickly scheduled for production.

Q: What quality tests does the product undergo before leaving the factory?

A: All products are assembled in a Class 100 cleanroom environment and undergo 100% dynamic bench testing at high temperatures and ultra-high pressures. We rigorously monitor pressure build-up, fuel return volume, and sealing performance to ensure the product meets quality standards for vehicle installation.

Q: What is the warranty period for the product?

A: We offer a 12-month warranty on this product. Should any malfunction occur due to non-human factors during the warranty period, we provide rapid after-sales technical support and service to protect your interests.