Yanmar N18 Plunger
Mega Marine supplies genuine and reconditioned plunger for Yanmar N18 marine engines, along with complete engines and a comprehensive range of spare parts. Fast RFQ response and global delivery.
The fuel injection pump plunger and barrel are a precision-matched pair that meter and pressurise fuel oil for delivery to the fuel injector. Ground to tolerances within 1-2 microns, the plunger generates injection pressures of 800-1,500 bar. The helical groove machined into the plunger controls the injected fuel quantity by varying the effective stroke as the fuel rack rotates the plunger.
Function in the Engine
Pressurises fuel oil to injection pressure, meters the precise quantity of fuel per injection event through the helical control groove, times the start and end of injection in coordination with the camshaft drive and fuel rack position.
About the Yanmar N18
Yanmar N-series 180mm bore medium-speed engine for propulsion and auxiliary applications in smaller commercial vessels.
Common Issues Requiring Replacement
Precision surface wear from abrasive particles in contaminated fuel, plunger and barrel seizure from water contamination or lubrication failure, erosion of the helix edge affecting fuel quantity and timing, corrosion from water or acidic fuel contamination.
Mega Marine supplies genuine OEM and quality reconditioned plunger for Yanmar N18 engines, with full traceability and global shipping to any port worldwide. We respond to quote requests within 4–6 hours.
- Engine Brand
- Yanmar
- Engine Model
- N18
- Part Category
- Plunger
- Condition
- Genuine & Reconditioned
Browse the full N18 parts range.
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