2TNV70 Yanmar 2TNV70 Specifications & Technical Data (2015—2026)

TNV Series Overview

The TNV series adds a whole range of “goodies” that make this engine a mechanical “Work of art.” The much acclaimed “Clean and Silent” TNE series has just become even better. It's called the TNV, and it stands for Total New Value. Let's take a look......

4. EGR Valve (≧37kW)

Modulation of the EGR valve by the engine control unit provides for the needs of all kinds of equipment.

Emission Reduction

Cleaner engines with even lower exhaust emissions are achieved by improving on the already excellent TNE base. Stricter emission standards are cleared by a wide margin.

IDI Engines

1. Combustion Chamber By investigating flow characteristics using experimental and numerical analysis methods, Yanmar research has achieved improved flow mixing in both the main chamber and the special mouth surrounding the injector. More efficient use of the incoming air charge results in cleaner burn and lower exhaust emissions. 2. Fuel Injection Equipment Mechanical Pump Instead of a PFR pump, a newly developed in-line pump has been used for the smaller TNV engines. Adjustments are made solely in the Yanmar’s own FIE factory ensuring precise compliance with regulations. Also the following features are incorporated: Increased force is applied by the governor to quicken the fuel controlling rack response time. Engine revs are more constant. Matching to a wide range of machinery is simplified. Emissions have been reduced by controlling fuel injection timing according to engine load. Cam profiles are matched to nozzle throttle needs, which give a better controlled injection rate. Emissions are reduced.

DI Engines

1. Nozzle Installation Angle The installation angle of the fuel injection nozzle is greater than that in conventional engines, so that uneven atomization of fuel between injections can be reduced. Excellent matching between intake swirl ratio and the shape of the combustion chamber has resulted in uniform mixing of fuel in the combustion chamber. Therefore, performance including combustion efficiency, startability, noise, and exhaust emission has been improved. On the 4TN94L, -98 and -98T by using 2 inlet and 2 exhaust valves, air intake and expulsion is markedly improved. Vertically mounted injector nozzle minimizes imbalance of spray pattern. 2. Combustion Chamber It increases the fluid energy of the air and fuel charge. The swirl effect produced in the chamber continues while combustion occurs, aiding mixing and results in lower exhaust emissions compared to conventional chambers.

Fuel Injection Equipment

MP Pump A new MP pump has been developed especially for the TNV engine series. Our aim was to make improvements over a wide range of areas to even further reduce emissions. Features are: High injection pressure Use of a mono plunger reduces uneven injection between the cylinders. Timing Control Device system optimizes injection to take into account speeds, loads and the startup phase. New mechanical governor helps to maintain cleaner exhausts. Minimal variation from chosen revs at low speed using constant pressure valve. Fuel Injection Nozzle Multiple numbers of very small holes are used to achieve uniform atomization. Holes are not simply drilled, their inside edges are carefully rounded to promote even flow and direction of spray, also to reduce resistance. Low sack nozzle profile improves combustion. Double corn shape protects from cavitation.