Description
Technical Overview & Product Details
The fuel injector assembly is mounted vertically into the center of the cylinder head cover, extending directly into the main combustion chamber cavity. In high-power, medium-speed four-stroke marine diesel engines like the Zichai L250 series (including the 6L250, 8L250, and LC9250 platforms), the injector must cycle reliably millions of times under high operating pressures.
Because the Zichai L250 series frequently runs on aggressive, viscous heavy fuel options like Heavy Fuel Oil (HFO) alongside Marine Diesel Oil (MDO), the L250-52-201 assembly features premium mechanical design elements. It incorporates a heavy-duty nozzle holder body, an internal high-elasticity pressure spring, a precise intermediate spindle, and a multi-hole spray nozzle tip fabricated from advanced heat-treated alloy tool steel.
- Compatible Engine Type: Zichai L250, LB6250, LB8250, 6L250, 8L250, and LC9250 series four-stroke medium-speed marine diesel engines.
- Part Number / Designation: L250-52-201 (Fuel Injector Assembly / Fuel Valve ASSY).
- Component Group: Fuel Injection System / Cylinder Head Fuel Equipment.
- Nozzle Coupling Matching: Works in direct configuration with Zichai high-pressure fuel pump lines and ZCK-series multi-hole nozzle tips.
- Fuel Compatibility: Fully optimized for low-and-high sulphur Marine Gas Oil (MGO), Marine Diesel Oil (MDO), and pre-heated Heavy Fuel Oil (HFO).
Key Features & Performance Benefits
- Micro-Atomized Fuel Spray Delivery: The internal multi-hole nozzle tip features micro-drilled spray orifices arranged at exact angles. This configuration maximizes fuel mixing with compressed charge air, reducing ignition delay and lowering Specific Fuel Oil Consumption (SFOC).
- Sharp, Anti-Drip Cutoff Action: Features a precision-lapped needle valve and seat assembly held by a high-tensile internal pressure spring. This layout ensures immediate, crisp valve seating at the end of the injection cycle, preventing post-injection fuel dripping that causes exhaust smoke and heavy carbon soot build-up.
- Superior Thermal and Corrosion Defense: The nozzle tip section faces continuous combustion temperatures exceeding 450°C. Our injectors are built using specialized hot-work alloy steels that resist thermal softening, needle sticking, and sulfur/vanadium ash corrosion.
- Stable Valve Opening Pressure (VOP): The heavy-duty internal spring assembly maintains its calibrated tension without experiencing premature relaxation. This ensures stable opening pressures across extended run times, keeping cylinder load distribution uniform.
Why Source from Heybeli Marine?
Sub-standard or worn fuel injectors suffer from low injection pressures, distorted spray geometry, and needle seizure. These faults cause immediate engine power loss, high exhaust gas temperatures (EGT), turbocharger fouling, and can lead to thermal piston crown cracking. Heybeli Marine secures your vessel assets and commercial schedules with:
- True OEM Geometric Precision: Sourced from world-class maritime fuel injection specialists, our injector assemblies match original factory flow rates, pressure thresholds, and dimensional envelopes perfectly.
- Global Strategic Fleet Inventory: We maintain deep stock allocations of Zichai L250 fuel system spares across our international logistics channels for immediate, 24-hour dispatch to major ports, dry docks, and shipyards globally.
- Comprehensive Matching Overhaul Kits: We supply the L250-52-201 assembly along with matching nozzle tips, copper sealing washers, high-pressure fuel pipes, fuel injection pumps, and complete cylinder head overhaul kits.
- Rigorous Pressure Bench Testing: Every single injector assembly undergoes thorough hydraulic pressure verification, opening pressure calibration, and spray pattern testing before being approved for distribution.
Technical Maintenance Note: During standard top-end overhauls or whenever high exhaust temperature variations are noticed on a cylinder unit, remove the L250-52-201 injector assembly and test it on a calibrated manual injector pump bench. Check and adjust the valve opening pressure (VOP) according to the values specified in the Zichai instruction manual using the internal adjustment shims or screws. Always renew the copper sealing washer at the bottom of the injector pocket during reinstallation; reusing an old, hardened washer will cause hot combustion gases to blow past the injector body, leading to localized head overheating and fuel varnish binding that makes future injector removal extremely difficult.