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Here's a good data link to the ship's engine.

2019/04/10 - [자동차 & 선박 디젤 엔진 ] - INSTRUCTION MANUAL HEAVY DIESEL ENGINES!!

2019/04/18 - [자동차 & 선박 디젤 엔진 ] - Ship Engine Basic Configuration

2019/04/19 - [자동차 & 선박 디젤 엔진 ] - SHIP Turbo blower(TURBO CHARGER), Air cooler, Exhaust manifold

This time, we will learn about ship engine Fuel Oil, ship engine Lubricating Oil, ship engine Cooling Water

(Write an example of one model, not all engines are the same. Please note.)

Fuel oil

Engine performance depends largely on the quality of fuel oil.

Use oil which meets the JIS light oil No. 2 specifications (JIS K2204) for your Diesel engine. When using heavy oil A, make sure that it meets the JIS specifications of heavy oil Class 1, No. 2 (JIS K2205). If poor quality fuel oil is used, adverse effecta — abnormal wear to the plungers and nozzles, engine output drop due to carbon accumulation in the combustion chambers, and lubricating oil aging — will result. Pump up fuel oil via a filter into the storage tank, and allow the fine particles of foreign matter contained in the fuel oil to settle, and use only the clean part of the fuel oil in the upper part of the tank. Exercise care not to let foreign matter in to the fuel oil tank when supplying it to that tank.

Engines operating on kerosene can be manufactured to optional specifications. Kerosene-burning engines require a special kind of fuel injection pumps because kerosene has extremely low lubrication quality and viscosity.

Fuel oil properties

Fuel oil for diesel engines must meet the requirements that it burns well and produces as little harmful substances from its burning as possible. Specifically, fuel oil must satisfy the following:

(1) Proper viscosity

Generally, fuel oil can be burnt with satisfactory results if the fuel is atomized in as fine and uniform particles as possible. Viscosity is the most important factor which influences fuel atomization.

(2) Small carbon residue and ash content

The amount of carbon residue and ash do not directly affect fuel burning. Generally, how-ever, carbon residue and ash hardly burn within the engine operating temperature range, and accumulate inside the cylinders to make the piston rings sticky and hasten wear to various parts of the engine.

(3) Small sulfur content

Sulfur is present in fuel oil as a component of a compound containing high molecular hydro-carbons. It changes into sulfurous gas and then into sulfuric gas when it is burnt, and causes the cylinder liners and piston rings to become corroded and worn.

(4) Small water content

Much water content in fuel oil will lower its heating value, cause the engine to become rusty, make the valves sticky, and produces ill effects by combining with the burnt sub-stance of sulfur content.

(5) Cetane number

Cetane number indicates the ignition quality of diesel engine fuel oil.

(6) Others

In addition to the above, vanadium in ash poses a problem because it is burnt into vanadium oxide which serves as a catalyst for producing sulfuric acid. At high temperature, a vanadium attack will occur to damage the combustion chamber.

Lubricating oil

Use a recommended brand of lubricating oil for your engine. Unless lubricating oil has suf-ficient viscosity at the maximum temperature that the lubricated parts of the engine reach, the engine will become seized due to a broken oil film.

Lubricating oil must have such a degree of viscosity as will not make a cold engine start dif-ficult at low temperature, and contain as little carbon residue as possible to assure great stability against various kinds of chemical reactions.

Grade CC or CD under the service classification of the API (American Pettoleum Institute) equivalent to SFA30 is

appropriate as lubricating oil for your engine.

The recommended brands of lubricating oil for your engine are shown below.

CAUTION: Never mix different brands of lubricating oil even if they are recommended brands.

Recommended Brands of Lubricating Oil (Fuel oil: light oil, heavy oil A)

(1) Action and properties of lubricating oil

Lubricating oil works mainly as follows:

(a) Lubrication

Lubricating oil forms an oil film over the working parts to reduce frictional resistance and wear.

(b) Cooling

When supplied at an appropriate rate, lubricating oil carries away the frictional heat generated by the frictional resistance of the working parts and keeps the working parts under a specific temperature level.

(c) Cleaning

Lubricating oil carries away burnt residues and the sludge generated by the aging of the lubricating oil itself to keep the working parts, piston rings and other internal engine parts clean.

(d) Sealing

Lubricating oil forms an oil film around the cylinder liners to assure smooth movement of the piston rings and improve their sealing effect.

(2) Properties of lubricating oil

The following properties are generally required of lubricating oil for diesel engines.

(a) Appropriate viscosity

Viscosity is the most important of all requirements for lubricating oil. If lubricating oil has too low a viscosity, its oil film cannot withstand high pressure. If it has too high a viscosity, frictional resistance will increase so that, in some cases, an oil film may not be formed due to a sluggish oil flow.

(b) High flash point

A high flash point is desirable for the stability of lubricating oil because it is exposed to high temperature at the pistons.

(c) Low pour point.

(d) Excellent stability against oxidation and non-corrosive to engine parts.

(e) Excellent thermal stability to resist carburizing and emulsifying when lubricating oil is exposed to high temperature.

(f) Excellent detergency and dispersion

To carry away the sludge which accumulates inside the engine, prevent sludge in lubricating oil from coagulating, and disperse it to prevent wear and corrosion.

(g) Good acid neutralizing action

An appropriate alkali number is required because lubricating oil is subject to oxidation under various adverse conditions.

Cooling water

The engine may be cooled by fresh water.

If hard fresh water is used, scale will stick to the cooling water passages and, particularly, the cylinder heads will be prevented from being properly cooled and possibly develop cracks.

Cooling water quality when using fresh water

It is very important to be well aware of the quality of cooling water for the engine. Even when fresh water is used, various parts of the cooling water system may become corroded, or collect scale or slime depending on the substances dissolved in the water.

Generally, corrosion of the engine cooling water system is often caused by various kinds of chlorides, typical of which is chloric ion (Cl-).

Besides, it is necessary to know pH, electric conduction, M-alkalinity, ammonia content, etc. as factors for determing the corrosiveness of cooling water.

cale trouble is mostly caused by calcium (Ca) and magnesium (Mg) in the cooling water.

Scale will lower the cooling effect of each cooler and cause cracks in the high-temperature part of the cylinder heads, etc. In addition, silicic acid (SiS2), manganese (Ma), and iron (Fc) must be borne in mind as elements causing formation of hard scale.

Therefore, it is necessary to analyze water to determine suitability as engine cooling water if the engine is to be used without troubles over a long period of time.

NOTE; Please inform us of the-results of a water Analysis.

It is recommended that. an inhibiter be added to cooling water for your engine.

(Write an example of one model, not all engines are the same. Please note.)