Diesel Engine Parts, Products

1. Product Technical Specifications

1. OEM Part No.: 3964141 (replaced supersession part: 5446734)
2. Applicable Engine: Cummins ISLe / QSL9 / ISDe 6L diesel engine (6-cylinder diesel, fits the 1st cylinder exclusively; matching serial parts: 3964142 for Cyl2-5, 3964143 for Cyl6)
3. Material: Seamless high-strength carbon alloy steel pipe with anti-rust galvanized surface treatment
4. Working Pressure: Rated working pressure 1350–1600 bar, peak instantaneous impulse pressure up to 1800 bar (common rail high-pressure fuel system standard)
5. Structure & Dimension: Custom bent integral pipe with double-end 60° conical sealing joints; single-piece finished bending without secondary welding; gross weight approx. 0.32–0.38kg per piece
6. Operating Temperature Range: -40℃ ~ +180℃ (resists engine compartment high-temperature radiation)
7. Quality Grade: Genuine OEM / aftermarket replacement available; normal warranty: 3–6 months

2. Installation Position

• Installed on the upper side of the ISLe engine cylinder head, within the engine valve cover outer area
• One end (large conical connector): Connects to the high-pressure outlet port of the engine common fuel rail;
• The other end (small conical connector): Fastened to the fuel inlet port of the No.1 cylinder fuel injector directly
• Arranged with fixed clearance away from exhaust manifold and high-temperature components to avoid thermal aging and abrasion; mounted with preset pipeline bending to eliminate assembly stress and engine vibration friction

3. Core Functions

1. High-pressure diesel delivery: Transports high-pressure pressurized diesel from the common rail to the No.1 cylinder injector steadily, maintaining stable common rail fuel pressure for accurate injector atomization and combustion
2. Sealed pressure maintenance: Zero internal leakage design locks system high fuel pressure; prevents pressure loss that would cause unstable fuel injection, power drop or excessive fuel consumption
3. Vibration buffer: The pre-bent pipeline structure offsets engine mechanical vibration and fuel pressure pulse shock, protecting common rail and injector connecting threads from fatigue crack damage
4. System safety guarantee: Isolates high-pressure fuel circuit; avoids air intake into fuel system which leads to hard starting, engine jerk or misfiring of No.1 cylinder