The new 4JH series of marine diesel engines from Yanmar were released in 2014. Developed based on 30 years of experiences with the previous JH series of marine engines, the new engines are based on Yanmar’s new TNV series of industrial diesel engines and incorporate proprietary control logic for marine propulsion engines. The adoption of optimized combustion technologies and a common rail fuel injection system have enabled the engines to comply with stringent exhaust emission regulations while also satisfying customer requirements for good fuel economy, clean exhaust, and low noise and vibration. The electronic control system allows easy engine installation, communication with onboard navigation equipment, and connection to a joystick maneuvering system. Yanmar believes the new engines will delight customers and set a new standard in the pleasure boat market.
Yanmar’s JH diesel engine for small boats first went on sale about 30 years ago in 1985. Over that time it has been subject to an ongoing series of enhancements. In 2014 a new generation engine was born which is environmentally friendly engine with full electronic control including a common rail fuel injection system like those already used in automotive and industrial engines as a key technology. Because marine engines are always used adjacent to salt water, special technologies different from those used on automotive and industrial engines are required. The new 4JH-CR features high quality and reliability, incorporating the extensive experiences and special technologies built up in partnership with users over approximately 30 years with the previous JH engine.
One of the features of the JH engine is that it was based on Yanmar’s TNV industrial diesel engine. Similarly, the base engine for the 2014 4JH-CR is the latest TNV engine described in the Fall 2015 edition of Yanmar Technical Review. Accordingly, along with the extensive experience acquired from the past JH engine, the new 4JH-CR also incorporates numerous special technologies from Yanmar’s industrial and other small diesel engines. The new 4JH-CR also inherits all of the marine electronic control technologies built up by Yanmar over many years.
As of the spring of 2016, the four models in the new 4JH-CR product range are the naturally aspirated 4JH45 (33.1kW) and 4JH57 (41.9kW) and the turbocharged 4JH80 (58.8kW) and 4JH110 (80.9kW). As described in section 3.6 below, all models comply with international exhaust emission regulations such as the Tier 3 regulations of the US Environmental Protection Agency (EPA). The new models also maintain the same engine dimensions as their predecessors, ensuring that the new 4JH-CRs are suitable for users who want to install them as replacements.
