Description
Technical Overview & Product Details
The Mitsubishi UEC 60LS series (including the 60LS and 60LS-II configurations) represents an elite class of low-speed, two-stroke crosshead marine diesel engines utilized as primary propulsion machinery across the global merchant fleet, particularly in tankers and bulk carriers. Due to the enormous cylinder bore and structural layout of crosshead engines, the fuel injection system must deliver massive quantities of heavily pressurized fuel with supreme uniformity.
The 502A / 809A nozzle designations represent a micro-calibrated, multi-hole atomizing tip array engineered to withstand extreme continuous cyclical thermal stress and structural mechanical loads.
- Compatible Engine Type: Mitsubishi UEC 60LS and UEC 60LS-II series two-stroke low-speed main propulsion engines.
- Nozzle Type / Designation: 502A / 809A series execution.
- Component Type: Fuel Injector Valve Nozzle Tip Element.
- Material: Vacuum-hardened, high-grade alloy tool steel with enhanced micro-hardness and hot-strength profiles.
- Fuel Compatibility: Fully optimized for persistent operation with high-viscosity Heavy Fuel Oil (HFO), Marine Diesel Oil (MDO), and Marine Gas Oil (MGO).
Key Features & Performance
- Optimized Spray Angle & Micro-Geometry: Features precision-drilled spray orifices matched perfectly to the immense combustion chamber geometry of the UEC 60LS cylinder. This secures a flawless fuel-air mixing matrix, promoting total thermal efficiency while strictly preventing direct flame impingement on the piston crown or the cylinder cover.
- Instantaneous Hydraulic Cutoff: The needle-to-seat contact zone is precision-lapped to absolute sealing tolerances. This guarantees a razor-sharp fuel cutoff at the microsecond the injection cycle concludes, eradicating “after-drip” and preventing carbon coking, high exhaust gas temperatures (EGT), and smoky exhaust plumes.
- Superior Resistance to Abrasive Cat-Fines: Low-grade, unrefined marine heavy fuel oils frequently carry highly abrasive catalytic fines (aluminum and silicon oxides). The advanced metallurgical layout of our 502A / 809A tips delivers high resistance against orifice erosion and cavitation pitting.
- Thermal Distortion and Seizure Defense: Engineered with ultra-precise running clearances between the sliding needle and guide body. This structure avoids needle sticking or sluggish movement when the vessel transitions between ambient-temperature distillate fuel (MGO) and pre-heated, high-temperature heavy fuel oil (HFO).
Why Source from Heybeli Marine?
Sub-standard main engine fuel nozzles result in incomplete combustion, accelerated cylinder liner wear, thermal imbalance across units, and localized piston crown burning. Heybeli Marine secures your technical management and vessel machinery assets with:
- Full Physical Interchangeability: Sourced from premium global manufacturers utilizing high-end CNC and grinding technology, our nozzles guarantee exact dimensional fitment and flow-matching with original equipment parameters.
- Global Logistics & Supply Chain: We hold comprehensive stock allocations of Mitsubishi UEC series fuel injection parts within strategic international supply lines, ensuring rapid dispatch to major dry docks, trading ports, and freight forwarders worldwide.
- Strict Certification and Quality Controls: Every single 502A / 809A nozzle undergoes extensive flow-rate verification, pressure sealing validation, and geometric quality checks before being approved for distribution.
- Complete Overhaul Integration: We supply these high-performance nozzle tips along with all corresponding gas-tight copper sealing washers, pressure pins, and internal springs required for a complete, professional injector rebuild.
Technical Maintenance Note: When replacing nozzles on large two-stroke propulsion engines like the Mitsubishi 60LS, always check the opening pressure (pop pressure) using a certified manual injector test bench to comply with the engine’s instruction manual. Clean the fuel valve body thoroughly to clear out residual varnishing or heavy carbon deposits, and always implement brand-new sealing gaskets to guarantee gas-tight structural compression against the cylinder cover.

