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Tech Update- Engines

By Tony Kryzanowski

Cat’s C7 diesel engine with ACERT technology is an in-line, six-cylinder engine with 439 cubic inches displacement. ACERT technology combines incremental improvements in fuel delivery, air management and electronic control to optimize engine performance and to meet emissions regulations.

 The clean-burning engine allows oil change intervals to be extended to 500 hours. The C7 is proven in Caterpillar forestry machines, wheel skidders, medium size wheel loaders and in on-highway trucks. It has a flat and long peak power curve for quick response in the working rpm range. At the heart of the patented ACERT technology is the ADEM A4 advanced electronic controller. It integrates and controls engine functions and combines with the common rail fuel system, smart waste gate turbocharger and crossflow head design for precise fuel and air delivery, which contributes to reduced emissions and strong engine performance.

John Deere
The John Deere PowerTech Plus engine is featured in a number of forestry machines. The PowerTech Plus engine family is composed of 13.5 L, 9.0 L, 6.8 L and 4.5 L models, offering a Tier III solution. Compared to their Tier II counterparts, the PowerTech Plus Tier III engines feature improved performance characteristics such as increased levels of power bulge, higher peak torque levels, greater low-speed torque, improved transient response, and better cold weather starting. PowerTech Plus engines also offer best-in-class fuel economy, the company says.

 New versions of the PowerTech Plus engine installed in John Deere’s new line of Eco III forwarders feature maximum output up to six per cent higher than before, depending on the model, improved torque in low work rpms, faster transient response, a cooled exhaust gas regulations system, variable geometric turbocharger, four-valve cylinder head, a high pressure common rail fuel system in all models, viscous fan clutch as standard equipment, and improved engine diagnostics.

Cummins’ new generation of Quantum System (QS) engines offer every Tier III/Stage IIIA solution, for every type of equipment and for every environment. From the compact QSB to the high-power QSK19, these engines go beyond meeting Tier III/Stage IIIA emissions to offer more responsive power delivery, a major reduction in noise and minimal maintenance requirements.

The Cummins design solution for Tier III/Stage IIIA is the development of in-cylinder advanced combustion, avoiding the need for additional engineering complexity. As a further performance enhancement, high pressure common rail fuel systems are incorporated in the QSB, QSC, QSL, and QSK19 engines. By achieving lower piston temperatures and lower cylinder pressures, Cummins Tier III/Stage IIIA engines operate with less mechanical stress, even under tough operating conditions. This translates into higher levels of engine durability.

Clean combustion reduces the level of soot in the engine oil, enabling long intervals between oil changes to be maintained. Beyond this, only minimal maintenance intervention is required. Overhead valve set checks at 5,000 hours for QSB, QSC and QSL as well as 1,500 hours for QSM, QSX and QSK19 exceed industry standards.

SisuDiesel’s new three-, four- and six-cylinder Citius series engines are designed for demanding off-road machinery applications. Robust construction, durability, reliability and strong torque are all features of the company’s engines.

To fulfill the more stringent emission requirements, several significant improvements have been introduced that improve the combustion process. These technical changes further strengthen the best properties of these engines. High injection pressure, precise electronic injection timing and effective charge air cooling are the major factors in emission control. The solutions used for reducing emissions have simultaneously enabled the increase of power density and torque level while maintaining good fuel economy.

Citius engines are said to be fast in response. The state-ofthe- art electronic control, high pressure fuel injection and turbocharger enable the engine to react without delay in changing load conditions. Traditional, strong SisuDiesel basic design, wet cylinder liners and charge air cooling are the foundation for long service life, which also reduces the overall hourly operation cost.