Reliable and Durable for Marine Conditions

The Weichai WP4.1N 88–140 kW marine engine features newly designed structural parts, including the block, cylinder head, pistons, and bearings, produced at Weichai’s Rui Power base. In addition, Weichai’s global supplier system ensures stable quality for all key components. The engine also benefits from a dust-free and constant-temperature assembly workshop, along with high-precision test benches, which help secure long service life and consistent reliability during marine operation.

Strong Power with Continuous Output

The WP4.1N delivers strong torque in the low and middle speed range, allowing vessels to accelerate smoothly and maintain stable pulling power. Its electronic-control unit provides precise control with high injection pressure, giving the engine excellent acceleration performance. At 50 percent of the rated speed, the engine can reach up to 132 percent of the rated torque, which helps vessels handle heavy loads and changing sea conditions.

Fuel-Efficient and Cost-Saving

The engine uses high-pressure common-rail technology with a Bosch fuel system and Weichai’s self-developed ECU to control injection volume accurately. Because of this setup, the WP4.1N keeps fuel consumption as low as 191 g/kW·h. In addition, the oil change interval of 500 hours or more helps reduce maintenance cost and daily operating expenses.

Smooth, Quiet, and Environment-Friendly

Through detailed NVH optimization, the engine reduces vibration and noise to create a more comfortable working environment. The gear chamber cover, cylinder head cover, and closed flywheel housing further help limit noise leakage. At the same time, the multi-stage electronic-control injection greatly reduces vibration during operation. The WP4.1N meets IMO Tier II and China Stage II emission requirements.

Practical, Flexible, and Easy to Integrate

The WP4.1N offers optional equipment such as vibration-isolating mounts and a manual priming pump to meet different customer needs. Moreover, the control system supports multiple signal inputs and outputs for automated control. Because of its flexible control strategies and stable performance, the engine adapts well to various marine applications and ensures reliable operation.