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Tuesday, 11 November 2025 12:44

MAN L21/31; Cylinder Unit (Code P50515-19)

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The cylinder unit, code P50515-19, represents the core combustion module of the MAN L21/31 engine, consisting of the cylinder liner, piston, piston rings, connecting rod, and associated components. This integrated assembly is engineered to withstand extreme pressures and temperatures generated during the combustion process. Its high-performance design ensures efficient power generation, minimal wear, and ease of replacement during overhauls. As the heart of each engine cylinder, the unit is vital for delivering reliable propulsion and energy output over long operational cycles.

The cylinder head top cover, code P50510-08, serves as a protective enclosure for the upper portion of the MAN L21/31 cylinder head, shielding internal components such as valve gear and injectors from dirt, debris, and external damage. It also contributes to oil retention and thermal insulation. Designed with precision to ensure a tight seal and easy access during servicing, the top cover plays an important role in maintaining engine cleanliness and mechanical integrity in demanding environments.

Tuesday, 11 November 2025 12:41

MAN L21/31; Indicator Valve (Code P50508-07)

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The indicator valve, code P50508-07, is a crucial diagnostic component mounted on the MAN L21/31 cylinder head, enabling engineers to measure internal cylinder pressure during engine operation. By allowing temporary access to the combustion chamber, it facilitates performance analysis through indicator diagrams and helps detect abnormalities such as misfiring, loss of compression, or injector malfunction. Its robust construction ensures safe operation under high-pressure conditions, making it an indispensable tool for preventive maintenance and engine tuning in marine and industrial applications.

The ball-shaped cup coded K 28041 is a key interface element in the rocker arm assembly of the ZV40/48 diesel engine. Designed to provide a smooth contact surface between the pushrod or adjustment screw and the rocker arm, it accommodates slight angular movements while minimizing friction and wear. Its spherical shape allows for even distribution of force, reducing stress concentrations and extending component life. Precision-manufactured from hardened materials, this cup ensures quiet, smooth rocker arm operation and contributes to the longevity of the valve gear system.

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