Yanmar 6EY18LW, 6EY18ALW Diesel Engine Service Manual

This project guide was prepared as reference when planning the implementation of a Yanmar marine auxiliary diesel engine. Accordingly, no details of engine accessories are included; they are decided separately based on the subsequent consultations.

Due to improvements to the product and other reasons, the descriptions in this Project Guide are subject to change without prior notice. Please check the specifications, performance, etc. of the product by the delivery specifications, drawings of finished product, operation manual and individual consultations.

Major Specifications of Engine
The specific fuel consumption shows the lower calorific value, 42.7 MJ/kg (10,200 kcal/kg), ISO3046/1, of a bare engine unit operated at 4/4 load and at rated speed and under the condition of complying with NOx emission regulation value (the tier 2 regulation) as required by IMO. When the engine-mounted lubricating oil pump is driven, 3 g/kWh is added to the consumption and when the cooling water pump is driven, 1 g/kWh is added to the consumption per one pump.

Definition of Engine Power and the Specific Fuel Consumption of 6EY18(A)LW Engine
Measure the engine power (output) at the shaft end. Do it when the engine is equipped with the auxiliary equipment, which represents the standard installation necessary for engine operation and is constantly driven by the engine's power (Auxiliary Equipment A under ISO 3046/1-1986 (E); in the case of this engine, the lubricating oil pump and the freshwater pump). If the use of other power sources is inevitable to drive this auxiliary equipment, the power required to drive such equipment is deducted from the engine output.

Measuring Conditions

  • Running in trial: 30 h
  • Ambient temperature: 25 °C
  • Atmospheric pressure: 100 kPa
  • Humidity: 30 % Water temp. at air cooler inlet: 25 °C
  • Exhaust gas back pressure: 3.43 kPa or below
  • Fuel oil: No.2, Class 1, JIS K2205 (M.D.O.), standard lower calorific value 42700 kJ/kg
  • Lubricating oil: Viscosity 30 or 40 of SAE J300b, properties of API service category CD.

Correction of Specific Fuel Consumption
When the engine mounted lubricating oil pump is driven, 3 g/kWh is added to the above specific fuel consumption. When the cooling water pump is driven, 1 g/kWh is added to the specific fuel consumption per one pump.

Exhaust Gas Emissions
The exhaust gas, although in extremely small quantities, contains CO2, NOx, CO, SOx and HC. The exhaust emissions, ultimately, cause acid rains, photochemical smog, air pollutions and global warming. The reduction of exhaust gas emissions now represents an important theme for engine manufacturers.

Notably, the IMO in 1997 adopted a protocol supplementing the existing oceanic pollution prevention treaty with the annex "Regulations on Air Pollution Control Law from Marine Vessels" to prevent air pollution by ships. The regulation on NOx emissions went into effect in May 2005. In October 2008, the revision of the annex was adopted and the tier 2 regulation went into effect on January 1, 2011.

The 6EY18(A)LW is an environmentally-friendly engine and, as other conventional Yanmar engines, employs the ASSIGN combustion system. The 6EY18(A)LW, without the use of special equipment, passes the values set by the IMO NOx emission standards Tier 2. Fuel consumption and exhaust conditions are good.

Freshwater/Freshwater Mixing Cooling System
The 6EY18(A)LW has a dual cooling system: the engine is cooled by high temperature freshwater and the auxiliary equipment is cooled by low temperature freshwater. The air cooler cools the air in two steps, with high temperature freshwater and low temperature freshwater. As an option for low load operation, an automatic bypass valve can be equipped on the inlet of the low temperature freshwater side of the air cooler. This valve bypasses the low temperature freshwater, so that the boost air can be heated at the air cooler for long continuous low load operation.

Yanmar 6EY18LW, 6EY18ALW Diesel Engine Repair Manual

Yanmar 6EY18LW, 6EY18ALW Diesel Engine Repair Manual For Free

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