Description
Technical Overview & Product Details
In the Yanmar 6N18 valve mechanism, the use of a dual-spring (inner and outer) design is a strategic choice to manage high-frequency oscillations. The 145610-11131 inner spring serves as a harmonic damper, preventing “spring surge” and ensuring that the valve closes rapidly and cleanly at high RPMs.
Manufactured from high-tensile, stress-relieved steel, this inner spring is subjected to constant compressive force. It is built to maintain its spring rate and structural integrity throughout the demanding duty cycles of main marine propulsion and auxiliary power generation.
- Compatible Engine Type: Yanmar 6N18 (A)L-V series marine propulsion and auxiliary engines.
- Part Number / Designation: 145610-11131.
- Component Type: Inner Valve Spring.
- Material: Premium-grade, fatigue-resistant alloy spring steel.
- Application: Inner position within the dual-spring valve assembly.
Key Features & Performance
- Harmonic Vibration Control: Engineered with a specific spring rate to act as a secondary damper, effectively neutralizing valve train resonance and preventing “valve float.”
- Reliable Closing Force: Complements the outer spring to maintain consistent valve-to-seat contact pressure, which is vital for preventing gas blow-by and protecting the valve face from overheating.
- Exceptional Fatigue Strength: Specifically treated to resist stress relaxation and permanent set, ensuring the valve timing remains accurate over thousands of operating hours.
- Precision Compatibility: Designed with exact dimensions to fit perfectly within the outer spring, ensuring concentric operation and preventing coil binding during maximum valve lift.
Why Source from Heybeli Marine?
Degraded inner springs can lead to erratic valve timing and severe damage to the engine’s top end. Heybeli Marine protects your vessel’s operational availability with:
- Strict OEM Interchangeability: Our 145610-11131 springs are manufactured to meet Yanmar’s exact engineering standards, ensuring perfect synergy with the valve train assembly.
- Global Strategic Logistics: We maintain a comprehensive inventory of essential 6N18 valve train spares, guaranteeing rapid dispatch to your vessel or shipyard, anywhere in the world.
- Quality Assurance: Every spring undergoes rigorous load-testing and dimensional inspection to ensure consistent performance and reliability under heavy maritime duty.
- Complete Overhaul Support: We provide these inner springs alongside our outer springs (145610-11121), retainers, and collets as part of a comprehensive, high-quality valve train rebuild kit.
Technical Maintenance Note:
During a cylinder head overhaul, both the inner and outer springs must be inspected and measured for free length against the Yanmar technical manual specifications. Even if the spring shows no visible damage, it is essential to replace the 145610-11131 if it is outside the manufacturer’s tolerances. We strongly recommend replacing inner and outer springs as a complete set per valve to ensure uniform tension and prevent uneven wear across the cylinder head. Always ensure that the springs are seated correctly on the cylinder head and retainers to avoid misalignment during operation.