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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 - 10000900 suitable for MWM & Deutz engines
ROCKER ARM - 10000900 suitable for MWM & Deutz engines

Precise Rocker Arm with Comparison Number 10000900 Discover the rocker arm with the comparison number 10000900, an essential OEM spare part for your engines. This product falls under the category of valve train components and ensures outstanding performance. With this comparison number, you can find the suitable part for your specific engine requirements.Optimal Solution for Marine and Stationary Applications This OEM spare part is suitable for MWM & Deutz engines. The strong compatibility provides you with a reliable solution for your needs. Trust in the robust characteristics that ensure long-term operation.

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ROCKER ARM - 02159887 suitable for MWM & Deutz engines
ROCKER ARM - 02159887 suitable for MWM & Deutz engines

Timeless Efficiency with Rocker ArmThe rocker arm (comparison number: 02159887) is an essential OEM spare part for the valve train in engines. Weighing 0.37 kg, it combines lightness with robustness and has been specifically designed for use in demanding environments. This product ensures that your machines can deliver full performance at all times.

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Sale price: €378.00 Regular price:€420.00(10% saved)
ROCKER ARM - 21242533 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 21242533 suitable for Volvo/Volvo Penta engines

Suitable Component: Rocker Arm Comparison Number 21242533Discover the rocker arm with the comparison number 21242533, an essential product in the group of valve train components. This component ensures that all movement processes in the engine harmonize efficiently. The rocker arm is compatible with Volvo/Volvo Penta engines and is ideal for applications in demanding environments.Easy Installation for Optimal Engine PerformanceWeighing only 0.25 kg, our rocker arm can be easily mounted and secures the essential functionality of your engine. This OEM replacement part is specifically designed for Volvo/Volvo Penta engines, allowing you to utilize the quality of a brand component for optimizing your engines’ performance.

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ROCKER ARM - 196D43702 suitable for MTU engines
ROCKER ARM - 196D43702 suitable for MTU engines

Precise Rocker Arm Product for Your Needs The rocker arm with the comparison number 196D43702 is a crucial OEM replacement part in valve train applications. Designed for users who need a suitable product, this rocker arm ensures that your engines operate reliably and efficiently. Our over 25 years of experience in the industry affirms the quality of our products, so you can always depend on them.

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ROCKER ARM - 12159687 suitable for Deutz engines
ROCKER ARM - 12159687 suitable for Deutz engines

Rocker arm replacement part with comparison number 12159687Experience the powerful replacement part you need with our rocker arm. The comparison number 12159687 ensures precise identification and makes this OEM replacement part the ideal solution for your specific requirements. With a weight of only 0.137 kg, the rocker arm is compact yet robust and optimal for use in various engines.

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Sale price: €218.26 Regular price:€242.52(10% saved)
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ROCKER ARM - 21448926 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 21448926 suitable for Volvo/Volvo Penta engines

Reliable Product: Rocker Arm for EnginesThe rocker arm with the comparison number 21448926 is an essential spare part, perfectly suited for Volvo/Volvo Penta engines. As an efficient rocker arm, it plays a crucial role in the functionality of the valve train and ensures that your engine delivers reliable performance. Weighing only 0.125 kg, this product integrates seamlessly into your application.Functional Integration for Top-Quality EnginesThis rocker arm is ideally suited for engines that require outstanding performance. It is designed as an OEM spare part, meaning it meets high-quality standards. The comparison number 21448926 is not just a number, but a testament to durability and optimal functionality in your engine.

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Sale price: €110.10 Regular price:€122.33(10% saved)
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ROCKER ARM - 4720504034 suitable for MTU engines
ROCKER ARM - 4720504034 suitable for MTU engines

First-Class Rocker Arm with Comparison Number 4720504034Discover our excellent product, the rocker arm with the comparison number 4720504034. This OEM replacement part is specifically designed to ensure the performance of your engines while maintaining consistent quality. Precisely manufactured, this rocker arm meets all requirements for the valve train.Compatibility with MTU EnginesThe rocker arm is suitable for MTU engines and meets the highest standards. By using OEM replacement parts, your engines gain longevity and efficiency, which are crucial for applications in the marine or stationary sector as well as in locomotives.

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Sale price: €343.68 Regular price:€381.86(10% saved)
ROCKER ARM - 12275243 suitable for MWM & Deutz engines
ROCKER ARM - 12275243 suitable for MWM & Deutz engines

Precise Rocker Arm Product with Comparison Number 12275243Discover our rocker arm product with the comparison number 12275243, an essential component that is perfectly tailored to the requirements of engines. This OEM replacement part ensures flawless function and precision to maximize the efficiency of your machines.

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ROCKER ARM - 04284303 suitable for Deutz engines
ROCKER ARM - 04284303 suitable for Deutz engines

Premium Rocker Arm: Your SolutionDiscover our OEM replacement part, the rocker arm with comparison number 04284303. This product is suitable for Deutz engines and provides you with an excellent solution for the valve train. Rely on top-quality materials that meet the high standards of engine manufacturing.Reliability of OEM Replacement PartsThe rocker arm offers outstanding performance and durability, suitable for Deutz engines. With the comparison number 04284303, you can be sure that you are purchasing a quality OEM replacement part tailored to your needs.

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Sale price: €134.61 Regular price:€149.57(10% saved)
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ROCKER ARM - 29273004 suitable for Deutz engines
ROCKER ARM - 29273004 suitable for Deutz engines

Valve Train Component: Rocker Arm from MOPA Discover our Rocker Arm (Comparison Number: 29273004) as an outstanding product in the category of valve train components. This OEM replacement part is compatible with engines that must meet the highest requirements. As a suitable component for Deutz engines, it is essential for optimal functionality and longevity. Weighing only 0.108 kg, this Rocker Arm offers a practical combination of robustness and efficiency.Ideal Choice for Demanding EnginesOur extensive range includes over 1 million components, so you can be sure to find the right product for your needs. This part is a suitable OEM replacement for a variety of manufacturers, including MWM, Mercedes-Benz, MAN, Volvo, MTU, Bosch, and Detroit Diesel. Rely on our selection when searching for reliable replacement parts.

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Sale price: €206.86 Regular price:€229.84(10% saved)
ROCKER ARM - 4720503234 suitable for MTU engines
ROCKER ARM - 4720503234 suitable for MTU engines

Reliable Rocker Arm: Your Essential ProductThe rocker arm with the reference number 4720503234 is an indispensable OEM replacement part. This product belongs to the category of valve train components and ensures optimal performance in engines suitable for MTU. Modern manufacturing techniques ensure a long lifespan.Suitable Solution for MTU EnginesThe reference number 4720503234 makes this rocker arm a suitable replacement part for MTU engines. With us, you will find exclusively OEM replacement parts that meet the highest standards. These products are specifically designed to meet the unique requirements of engines suitable for MTU.

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ROCKER ARM - 5800550001 suitable for MTU engines
ROCKER ARM - 5800550001 suitable for MTU engines

Reliable Rocker Arm Replacement Part for EnginesDiscover our Rocker Arm OEM replacement part (part number: 5800550001), specially designed for the valve train. This product offers a quality solution for the operation of engines that depend on premium quality.Optimized Performance for MTU EnginesOur Rocker Arm is compatible with MTU engines and ensures optimal efficiency. With the part number 5800550001, you will find the ideal OEM replacement part to meet your specific requirements.

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ROCKER ARM - 360106450216 suitable for MWM & Deutz engines
ROCKER ARM - 360106450216 suitable for MWM & Deutz engines

Rocker Arm – Quality for Your Engine ApplicationDiscover the OEM replacement part rocker arm, comparison number 360106450216, specifically designed to optimize the performance of your MWM & Deutz engines. Weighing 0.497 kg, this product is robust and meets the highest standards of quality and reliability. The use of OEM replacement parts ensures a precise fit and the necessary reliability you need for the efficient operation of your engines.

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Sale price: €239.85 Regular price:€266.50(10% saved)
ROCKER ARM - 04006158 suitable for MWM & Deutz engines
ROCKER ARM - 04006158 suitable for MWM & Deutz engines

Premium Rocker Arm with Comparison Number 04006158 The rocker arm with the comparison number 04006158 represents an optimal solution for reliable engine performance. This product belongs to the category of valve train components and meets demanding standards for engines. Weighing only 0.18 kg, the rocker arm is ideally suited for various challenges in use.Perfectly Suitable for MWM & Deutz Engines This rocker arm is perfectly suited for MWM & Deutz engines, ensuring outstanding functionality. Our parts are precisely designed to optimize the lifespan and efficiency of your engine. Rely on our expertise for long-term engine maintenance.

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ROCKER ARM - 12310001 suitable for MWM & Deutz engines
ROCKER ARM - 12310001 suitable for MWM & Deutz engines

Precise Component: Rocker Arm 12310001Discover the rocker arm (comparison number: 12310001), an essential OEM replacement part for the valve train of your engine. This product is perfectly suited for MWM & Deutz engines and is used in marine and stationary applications. With compact dimensions of 10.5 cm in length and width, as well as 4 cm in height and a weight of only 0.236 kg, the rocker arm is easy to integrate and optimizes the operational performance of your engines.Quality from Reputable ManufacturersThe rocker arm is an OEM replacement part that offers the highest precision. With this quality, you can replace older or worn-out components suitable for MWM & Deutz engines. Trust in the durability and reliability of this product, which is based on market-leading standards and years of experience in the field.

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Sale price: €310.85 Regular price:€345.38(10% saved)
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ROCKER ARM - 22678889 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 22678889 suitable for Volvo/Volvo Penta engines

Rocker arm with comparison number 22678889 discoveredDiscover our rocker arm, compatible with Volvo/Volvo Penta engines, with the comparison number 22678889. This rocker arm weighs 2.991 kg and is an essential component to maintain the performance of your engines. Rely on the premium quality that is evident in this OEM replacement part.

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Sale price: €1,475.84 Regular price:€1,639.82(10% saved)
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ROCKER ARM - 5900500133 suitable for MTU engines
ROCKER ARM - 5900500133 suitable for MTU engines

Rocker Arm – Your Important ComponentDiscover our rocker arm product, comparison number 5900500133, which is optimally tailored to the requirements of engines. This OEM replacement part delivers the performance you expect and enhances the efficiency of your engine operation.

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Sale price: €3,633.58 Regular price:€4,037.31(10% saved)
ROCKER ARM - 02002466 suitable for MWM & Deutz engines
ROCKER ARM - 02002466 suitable for MWM & Deutz engines

Efficient Rocker Arm for Your NeedsDiscover our new product: the Rocker Arm, comparison number 02002466. This innovative OEM replacement part belongs to the category of Valve train components and is crucial for the operation of your engines. It has been developed specifically for MWM & Deutz engines, offering you the highest precision and reliability.Quality You Can Rely OnOur Rocker Arm ensures that your MWM & Deutz engines operate smoothly with excellent replacement parts. As an OEM replacement part, this product possesses the qualities necessary for durability and optimal performance – essential for professional applications.

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ROCKER ARM - 420129 suitable for Volvo/Volvo Penta engines
ROCKER ARM - 420129 suitable for Volvo/Volvo Penta engines

Rocker arm with comparison number 420129The rocker arm with the comparison number 420129 is a top-quality OEM spare part that is ideal for your needs. This essential product is part of the valve train components, suitable for Volvo/Volvo Penta engines. Weighing 0.218 kg, it offers both quality and reliability for long-lasting engine performance.Precision and Fit for EnginesThanks to its precise manufacturing, this rocker arm is the perfect choice as an OEM spare part regarding fit and functionality. It is suitable for particularly demanding operating conditions, ensuring optimal performance during continuous use.

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Sale price: €274.19 Regular price:€304.66(10% saved)
ROCKER ARM - 51042010026 suitable for MAN D-engines
ROCKER ARM - 51042010026 suitable for MAN D-engines

Discover the Rocker Arm for MAN D EnginesExplore our product, the Rocker Arm with the comparison number 51042010026. This Rocker Arm is a crucial component in the category of Valve train components and excels in every application. Weighing just 0.2 kg, the Rocker Arm is ideal for robust working environments suitable for MAN D engines.Quality through OEM Replacement PartsThe OEM replacement part meets high standards and is specifically designed to maximize the performance of your engine. This Rocker Arm is suitable for MAN D engines, ensuring smooth operation that you particularly need in marine and stationary applications.

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ROCKER ARM - 04254301 suitable for Deutz engines
ROCKER ARM - 04254301 suitable for Deutz engines

Precise Functionality with Rocker Arm – Reference Number 04254301Discover the exceptional precision of our rocker arm, listed under reference number 04254301. This high-quality OEM replacement part provides optimal functionality for your engine and is crucial for enhancing the performance of your machine.Suitable for Deutz Engines and MoreThis rocker arm is compatible with Deutz engines and has been specifically designed to support their robustness and efficiency. Weighing only 0.18 kg, it improves the operation of your engines and ensures everything runs smoothly. Each OEM replacement part facilitates easy installation and reliable performance.

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Sale price: €76.05 Regular price:€84.50(10% saved)
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ROCKER ARM - 8390500833 suitable for MTU engines
ROCKER ARM - 8390500833 suitable for MTU engines

Rocker Arm: Precision for Efficient EnginesDiscover our OEM replacement part, the rocker arm with the comparison number 8390500833. This product is designed to support the functionality of MTU engines, ensuring efficient operating costs while delivering maximum performance. Trust in the quality of the components developed for demanding engines in marine and stationary applications.

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Sale price: €17,495.84 Regular price:€19,439.82(10% saved)
ROCKER ARM - 8800500834 suitable for MTU engines
ROCKER ARM - 8800500834 suitable for MTU engines

Convincing OEM Replacement Part: Exhaust Rocker ArmDiscover our OEM replacement part, the Exhaust Rocker Arm, which optimally combines functionality and quality. With the comparison number 8800500834, this product delivers reliable performance for your engines. Thanks to precise manufacturing standards, this Exhaust Rocker Arm is suitable for applications that require robust performance.

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ROCKER ARM - 5500500234 suitable for MTU engines
ROCKER ARM - 5500500234 suitable for MTU engines

Rocker Arm suitable for MTU enginesThe rocker arm with the comparison number 5500500234 is a significant product within the category of valve train components. This OEM replacement part meets the requirements necessary to ensure the efficiency of MTU engines.

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Sale price: €2,536.08 Regular price:€2,817.87(10% saved)