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ROCKER ARM

ROCKER ARM Valve Train Components for Demanding Diesel and Gas Engines

Valve train components are the mechanical link between the camshaft and the combustion chamber, converting rotary motion into precise valve lift and timing. This category includes the ROCKER ARM, cam followers, hydraulic lash adjusters, pushrods, valve bridges, guides, springs, retainers, and associated shafts and bearings. In heavy-duty diesel and gas engines—whether propulsion units on a vessel or stationary power generation—the valve train defines how efficiently air enters and exhaust exits the cylinders, directly influencing output, fuel consumption, emissions, and service life. For purchasers and technical teams, choosing robust valve train components is a strategic decision that protects uptime and total cost of ownership.

Technical function: valve train components and ROCKER ARM in diesel engine and marine engine applications

The valve train controls intake and exhaust events with micrometer accuracy, cycle after cycle. The cam profile sets lift and duration; followers and tappets transfer that motion; the ROCKER ARM pivots it to the valve stem; springs stabilize the system and close the valves; guides and seats maintain alignment and sealing. In a diesel engine with high peak firing pressures, the ROCKER ARM must withstand enormous contact loads while keeping friction and wear under control. In a marine engine operating under variable load and continuous duty, consistent geometry and surface finish across all valve train components ensure smooth operation, low noise, and predictable maintenance intervals.

Modern ROCKER ARM OEM parts often integrate needle bearings or precision bushings at the pivot to minimize friction, plus hardened pads or rollers at the valve contact to resist pitting and scuffing. Materials range from forged alloy steels to surface-treated components (carburized, nitrided, or DLC-coated contact zones) that stabilize hardness and reduce micro-welding under boundary lubrication. Hydraulic lash adjusters within the assembly can compensate for thermal growth, maintaining valve lash within a tight window, safeguarding timing and valve seating during cold starts and hot running.

By keeping valve lift true to the cam profile, the valve train governs volumetric efficiency, turbocharger response, and cylinder scavenging. Stable dynamics at high rpm prevent valve float, protect against piston-to-valve contact, and maintain precise emissions control. A correctly engineered ROCKER ARM for marine engine duty also reduces parasitic losses, improving brake-specific fuel consumption and extending component life in challenging salt-laden environments.

  • · Precise timing and lift for clean combustion
  • · High load capacity under continuous-duty cycles
  • · Optimized friction via bearings, coatings, and finishes
  • · Stable valve lash and alignment across temperature ranges
  • · Durable materials and heat treatment against wear
  • · Compatibility with OEM parts interfaces and tolerances

Importance for engine operation: why valve train components matter

Reliability starts at the top end. Worn or misaligned valve train components create a cascade of issues: lash drift that alters timing, accelerated cam lobe and follower wear, rocker pad pitting, valve guide ovality, and spring fatigue. The immediate effects include hard starting, misfire under load, poor turbo spool, increased smoke, and rising exhaust temperatures. Over time, blow-by escalates and oil becomes contaminated with metallic debris, threatening bearings and turbocharger integrity.

Critical failures can be catastrophic. A seized ROCKER ARM or collapsed adjuster can lead to a dropped valve, valve-to-piston contact, or broken pushrods, resulting in major downtime and costly overhauls. Maintaining a robust valve train preserves compression, ensures clean combustion, and stabilizes emissions—key for meeting class and port requirements in a marine engine while protecting fuel economy and component longevity.

Advantages of OEM spare parts suitable for valve train components

Specifying OEM spare parts suitable for valve train components secures the exact geometry, metallurgy, and surface treatments the engine was engineered to run with. Tight tolerances in a ROCKER ARM, follower radius, or lash adjuster bleed rate are not “nice-to-have”; they are essential to keep the system in dynamic balance across the full operating envelope.

  • · Performance: Maintains designed valve lift, duration, and dynamics.
  • · Reliability: Consistent heat treatment and coatings resist scuffing and spalling.
  • · Budget: Lower lifecycle cost through longer service intervals and reduced collateral damage.
  • · Service life: Proven fatigue strength for continuous-duty diesel and gas engines.
  • · Fit and compatibility: Correct interfaces for shafts, pins, lash adjusters, and bridges.
  • · Predictable maintenance: Known wear patterns that align with engine manuals.

When sourcing ROCKER ARM OEM parts, purchasers gain confidence that contact geometry, hardness gradients, and bearing selections match the engine’s load spectrum—especially vital in high-BMEP diesel applications and marine engine environments where salt, vibration, and long run hours stress every component.

MOPA as your partner for OEM spare parts valve train components

MOPA is an experienced and reliable partner for OEM spare parts for valve train components. We support purchasers, shipowners, and technical managers with fast sourcing of ROCKER ARM assemblies, followers, bridges, adjusters, springs, and related hardware for diesel and gas engines. Our focus is speed, quality, and security in the trade of OEM parts—backed by transparent documentation, precise identification by engine model and serial, and logistics tailored to dock schedules and overhaul windows.

From single ROCKER ARM replacements to full top-end kits, MOPA streamlines the process: accurate part cross-referencing, prompt quotations, and shipment handling that minimizes laytime. You receive components that align with OEM specifications, helping your maintenance team return the engine to service swiftly and with confidence.

Conclusion

Valve train components—especially the ROCKER ARM—are central to power, efficiency, and the operational safety of diesel and gas engines. Specifying OEM spare parts suitable for valve train components preserves timing accuracy, reduces wear, and protects budgets through stable, long service intervals. With MOPA as your partner, sourcing the right parts becomes faster, safer, and fully aligned with the technical demands of marine and industrial operations.

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ROCKER ARM - 93216147019 suitable for MTU engines
ROCKER ARM - 93216147019 suitable for MTU engines

High-Quality Rocker Arm for Optimal Engine PerformanceDiscover the product Rocker Arm (comparison number 93216147019), suitable for MTU engines. This OEM replacement part is an essential component of the valve train components and ensures the efficient functionality of your engine.

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Sale price: €17.55 Regular price:€19.50(10% saved)
ROCKER ARM - 02021859 suitable for MWM & Deutz engines
ROCKER ARM - 02021859 suitable for MWM & Deutz engines

Rocker Arm for Efficient Engine OperationDiscover our OEM replacement part rocker arm (comparison number: 02021859), an essential product from the category of valve train components. Weighing 9.2 kg, this rocker arm ensures efficient functioning in engines, particularly in models that are suitable for MWM & Deutz. Quality and performance are our top priorities.Optimal Performance for MWM & Deutz EnginesThis rocker arm is suitable for MWM & Deutz engines and contributes to the smooth operation of your drive. Its robust construction ensures a long service life and enhances reliability. If you are looking for a part for maintenance or as an immediate replacement, our rocker arm is the ideal choice – exactly the OEM replacement part that meets your needs.

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ROCKER ARM - 12275620 suitable for Deutz engines
ROCKER ARM - 12275620 suitable for Deutz engines

Rocker arm suitable for Deutz – Quality that impressesExperience our rocker arm with the comparison number 12275620, an essential product in the field of valve train components. This OEM spare part, thanks to its lightweight of 0.222 kg, not only impresses with its user-friendliness but also ensures the efficiency of your engines. The rocker arm provides smooth operation of your machines.OEM spare parts are highly relevant for Deutz enginesThe rocker arm product is suitable for Deutz engines and meets high quality standards. As an OEM spare part, you benefit from the high-quality work required for reliable operation. Our internal controls ensure that all components undergo strict testing to maximize performance.

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ROCKER ARM - 12171800 suitable for MWM & Deutz engines
ROCKER ARM - 12171800 suitable for MWM & Deutz engines

Professional OEM Replacement Part for EnginesDiscover the rocker arm OEM replacement part with the comparison number 12171800. This durable product is essential for the proper functionality of your engines. As part of the valve train components, the rocker arm ensures precise valve control and ultimately optimizes engine performance. Rely on our replacement parts, as they stand for quality and compliance with OEM standards.Excellent Fit for MWM & Deutz EnginesOur rocker arm is compatible with MWM & Deutz engines, allowing for precise integration into various engine types. The accuracy and quality of the OEM replacement part mitigate potential risks associated with aftermarket products. Take advantage of the opportunity to keep your engine in optimal condition thanks to excellent components.

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Sale price: €456.30 Regular price:€507.00(10% saved)
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ROCKER ARM - 51042016196 suitable for MAN D engines
ROCKER ARM - 51042016196 suitable for MAN D engines

Quality Product: Rocker Arm with Comparison Number 51042016196Discover the Rocker Arm product with the comparison number 51042016196, which is ideal for your valve train requirements. This replacement part is an essential component of the category valve train components.Excellent Fit for Engines Compatible with MAN DThis Rocker Arm is suitable for MAN D engines and has been manufactured under strict standards. You can rely on this replacement part to provide optimal efficiency and durability. Each component ensures maximum performance of your diesel or gas engine.

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Sale price: €52.65 Regular price:€58.50(10% saved)
ROCKER ARM - 856627 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 856627 suitable for Volvo/Volvo Penta engines

Precise Product: Rocker Arm in DetailDiscover our quality-tested Rocker Arm OEM replacement part, comparison number 856627. This product is specifically designed to support the performance and efficiency of engines. Weighing only 0.168 kg, the Rocker Arm offers optimal operation, making it ideal for various applications.

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ROCKER ARM - X52405500124 suitable for MTU engines
ROCKER ARM - X52405500124 suitable for MTU engines

Rocker arm suitable for MTU enginesDiscover our OEM replacement part rocker arm, comparison number X52405500124, which is ideal for valve train components. This product ensures high performance in engines, as it has been specifically designed to remain reliably in operation.Advantages of OEM replacement partsOur rocker arm, suitable for MTU, ensures that you choose the right component for your machines. As an OEM replacement part, we offer a variety of options. Over the years, we have built a large inventory of spare parts that support your operational processes.

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Sale price: €312.85 Regular price:€347.61(10% saved)
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ROCKER ARM - 9060551210 suitable for MTU engines
ROCKER ARM - 9060551210 suitable for MTU engines

Rocker arm for effective engine performanceDiscover our top-quality rocker arm, an OEM replacement part from the group of valve train components. With the comparison number 9060551210, this product is precisely tailored to meet the needs of MTU engines. Count on the highest quality for optimal engine performance.

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Sale price: €32.41 Regular price:€36.01(10% saved)
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ROCKER ARM - 12313205 suitable for MWM & Deutz engines
ROCKER ARM - 12313205 suitable for MWM & Deutz engines

Precise Rocker Arm for Your ApplicationDiscover our rocker arm (comparison number: 12313205), a precise OEM spare part specifically designed for the valve train. This product weighs 0.318 kg and utilizes proven technologies for optimal functionality. The rocker arm is suitable for MWM & Deutz engines and meets high standards of quality and durability.Quality for MWM & Deutz EnginesThis rocker arm product contributes to the reliability of your engines. The rocker arm, in conjunction with OEM spare parts, not only offers durability but also stability and excellent performance. Benefit from the precise fit that our rocker arm provides, especially for MWM & Deutz engines.

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Sale price: €227.38 Regular price:€252.64(10% saved)
ROCKER ARM - 21415405 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 21415405 suitable for Volvo/Volvo Penta engines

Essential Rocker Arm for Valve Train The rocker arm, comparison number 21415405, is an essential product for the valve train components of engines. This OEM replacement part offers excellent fit and durability, making it ideal for the demanding requirements in marine applications.

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ROCKER ARM - 630006450016 suitable for MWM & Deutz engines
ROCKER ARM - 630006450016 suitable for MWM & Deutz engines

Optimal Support from the Rocker ArmDiscover our rocker arm with the comparison number 630006450016, an essential OEM spare part specifically designed for the engine performance of your systems. Weighing just 0.09 kg, this rocker arm is the ideal solution for optimizing the valve train of your machines.Precision Suitable for MWM & Deutz EnginesThis rocker arm is suitable for MWM & Deutz engines and ensures seamless integration into existing drive systems. Engine operations require precise control, and this is where our specific product comes into play. The accuracy and material quality of this OEM spare part ensure the performance of your machines and extend their lifespan.

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ROCKER ARM - 03311057 suitable for MWM & Deutz engines
ROCKER ARM - 03311057 suitable for MWM & Deutz engines

Strong Performance with Rocker ArmDiscover our rocker arm (comparison number: 03311057), an important valve train component that significantly contributes to the efficiency of your engines. This product is specifically designed for MWM & Deutz engines and offers excellent durability and functionality in critical applications.

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ROCKER ARM - 29273012 suitable for Deutz engines
ROCKER ARM - 29273012 suitable for Deutz engines

Valve Train Component – Rocker ArmDiscover the rocker arm replacement part with the comparison number 29273012, which serves as a crucial valve train component and is ideally suited for various applications. This product impresses with its durability and compatibility, providing a reliable solution for different motorized environments.Suitable for Deutz Engines!The rocker arm is specifically designed to fit Deutz engines and delivers top performance. Weighing just 0.094 kg, this OEM replacement part is particularly lightweight yet exceptionally robust. Benefit from the OEM quality that you can always rely on in industrial use.

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ROCKER ARM - 5600500033 suitable for MTU engines
ROCKER ARM - 5600500033 suitable for MTU engines

Top Quality: Rocker Arm suitable for MTU EnginesThe rocker arm with the comparison number 5600500033 is one of the efficient OEM replacement parts specifically designed for the valve train. This product offers the performance and durability that your MTU engines require.OEM Replacement Parts with Comparison Number 5600500033Our years of experience make us a reliable provider of OEM replacement parts. With the comparison number 5600500033, you receive a product suitable for MTU that optimally supports your engines in practice.

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Sale price: €7,166.64 Regular price:€7,962.93(10% saved)
ROCKER ARM - 21242550 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 21242550 suitable for Volvo/Volvo Penta engines

Versatile Rocker Arm for High-Performance EnginesDiscover the rocker arm with the comparison number 21242550, a precise product that provides essential valve train components in your engine. This OEM replacement part is your optimal choice to ensure the efficient operation of engines. The comparison number 21242550 is your key to quality and reliability.

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ROCKER ARM - 03373551 suitable for MWM & Deutz engines
ROCKER ARM - 03373551 suitable for MWM & Deutz engines

Rocker Arm as an Essential ComponentDiscover our rocker arm, an essential product that impresses with its quality. With the comparison number 03373551, this OEM replacement part is ideally suited to optimally support the performance of your engines. The component weighs only 0.21 kg and plays a crucial role in valve control.Suitable for Optimal Performance: MWM & Deutz EnginesThis OEM replacement part is suitable for MWM & Deutz engines and ensures improved efficiency and functionality. The use of high-quality materials provides a long service life and a high level of reliability. You can rely on the rocker arm to meet all requirements and deliver excellent performance.

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ROCKER ARM - 650046450024 suitable for MWM & Deutz engines
ROCKER ARM - 650046450024 suitable for MWM & Deutz engines

Efficient Rocker Arms for Demanding EnginesWe present the rocker arm with the reference number 650046450024, an indispensable product that serves as an essential valve train component for your engines. This OEM replacement part weighs 6.25 kg and is designed for flawless operation in challenging applications.Suitable for MWM & Deutz EnginesThe rocker arm is suitable for MWM & Deutz engines and is characterized by high precision and quality. Thanks to careful development according to manufacturer standards, you can rely on dependable performance and durability, which are necessary to ensure the efficiency of your machines in the long term.

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ROCKER ARM - 12850266 suitable for Deutz engines
ROCKER ARM - 12850266 suitable for Deutz engines

Rocker Arm Spare Part for Reliable PerformanceDiscover the rocker arm, an important component in the valve train, under the comparison number 12850266. This product ensures that your engines deliver optimal performance. The rocker arm is an innovative OEM spare part, specifically designed to meet the requirements of professional applications.Suitable for Deutz EnginesThis component is suitable for Deutz engines and plays a crucial role in the mechanics. Weighing only 0.106 kg, the spare part offers both stability and predictable performance in demanding environments. Rely on products designed for long-lasting dependability.

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Sale price: €105.71 Regular price:€117.46(10% saved)
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ROCKER ARM - 29273017 suitable for Deutz engines
ROCKER ARM - 29273017 suitable for Deutz engines

Precise Rocker Arm for Your Application AreaOur rocker arm with the comparison number 29273017 offers you the ideal solution for the requirements of your engines. This OEM replacement part is crucial for the valve train and enables the longevity of your engines. Weighing 0.105 kg, this product is perfectly suited for efficient operation and maintenance in various application scenarios.

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Sale price: €301.16 Regular price:€334.62(10% saved)
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ROCKER ARM - 51042016136 suitable for MAN D-engines
ROCKER ARM - 51042016136 suitable for MAN D-engines

Precise Rocker Arm with Comparison Number 51042016136The rocker arm with comparison number 51042016136 is an essential OEM replacement part that falls under the category of valve train components. This product is suitable for MAN D diesel and gas engines and provides the necessary precision for reliable engine performance. Weighing only 0.24 kg, this rocker arm design combines lightness with robustness.

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Sale price: €146.02 Regular price:€162.24(10% saved)
ROCKER ARM - 8800500533 suitable for MTU engines
ROCKER ARM - 8800500533 suitable for MTU engines

Premium Inlet Rocker Arm for Versatile ApplicationsDiscover our product, the Inlet Rocker Arm, with the comparison number 8800500533. This OEM spare part offers quality tailored for MTU engines and impresses with its excellent workmanship. The item is categorized under Hoses and meets all requirements for reliable operation.

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ROCKER ARM - 21753131 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 21753131 suitable for Volvo/Volvo Penta engines

Rocker Arm: Precision for Your EnginesDiscover our rocker arm (comparison number: 21753131), the essential product for the smooth operation of your engines. This rocker arm is crucial for efficiently controlling the valve movements in engines. Hermetically sealed and powerful, it ensures that your engine always runs optimally.Optimal Compatibility Through OEM Replacement PartsThe rocker arm is suitable for Volvo/Volvo Penta engines and ensures that they can operate precisely. Every OEM replacement part we offer is subject to strict quality controls, allowing you to rely on the durability and resilience of our products. Weighing only 0.006 kg, the product is lightweight yet extremely durable.

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ROCKER ARM - 4720503134 suitable for MTU engines
ROCKER ARM - 4720503134 suitable for MTU engines

Discover Our Rocker Arm Replacement PartDiscover our product, the rocker arm with the comparison number 4720503134, specially designed for the valve train of engines. This replacement part is essential for increasing the efficiency of your engine components.Suitable for MTU EnginesThis rocker arm is perfectly suited for motorized applications identified as compatible with MTU. Trust in the proven performance of the replacement parts that provide optimal functionality.

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ROCKER ARM - 650046450016 suitable for MWM & Deutz engines
ROCKER ARM - 650046450016 suitable for MWM & Deutz engines

Precise Control with the Rocker ArmDiscover our top-quality rocker arm (comparison number: 650046450016), an essential spare part from the category of valve train components. This product is perfectly suited for the demanding requirements of engines designed for MWM & Deutz. With over 1 million available spare parts in our range, MOPA Motorparts is your partner for top-notch solutions in the engine sector.

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