Diesel Generator Lubricating Oil Recommendations

Selecting the suitable specification of lubricating oil and fuel is very important for a engine. In this article, we still discuss Perkins 4000 Series diesel generator. The content mainly includes lubricating oil recommendations, engine operation, cooling system and fuel specification.

 TYPE OF OIL

The industrial diesel engine should be lubricated with a good quality oil conforming to API CD or CCMC D4 specifications. All the major oil companies formulate oils to the above specifications.

OIL CHANGE PERIODS

For normal operation of the engine the oil should be changed every 250 hours or annually whichever is the sooner.

Under certain circumstances where a centrifugal oil filter is fitted to the engine and an oil analysis programme has been carried out with the oil supplier over a period of 1000 hours of engine operation, it may be possible to extend the oil change period up to maximum of 350 hours.

To achieve this extended oil change period, a centrifugal oil filter must be fitted and cleaned every 250 hours between routine oil changes, and at every oil change point i.e. 350 hours maximum.

As the oil deteriorates it is essential that the following parameters must not be exceeded at the oil change point:

1. The viscosity of;the oil must not increase by more than 10cSt at 100℃.

2. The total base number of the oil should not reduce to less than 50% of the value of new oil.

3. The flash point of the oil should exceed 180℃.

4. The water content of the oil must not exceed l%.

5. The fuel content of the oil must not exceed l%.

6. Oil samples should be taken from the mean sump oil level of the engine.

ENGINE OPERATION

Excessive periods of idling or repeated cold starts should be avoided, as they will cause excessive dilution of the oil by fuel, requiring. more frequent oil changes and dangerously lowering the flash point of the oil.

Should there be a lubricating oil supply problem, or if the fuel being used contains more than 0.5% sulphur Perkins Engines (Stafford) Limited must be consulted to give advice in selecting a suitable grade.

The following list gives details of some of the oils that meet the required specifications, Note that the brand names may change as oils are upgraded or reformulated.

An up-to-date fist is maintained by Perkins Engines (Stafford) limited of major oil companies products and information, which can be obtained from Pekins Engines (Stafford) Service Department.

WARNING!! Failure to comply with these instructions will invalidate the warranty offered with the engine, as it may result in engine damage.

WARNING!! Always stop the engine and allow the pressurized system to cool before removing the filler cap. Avoid skin contact with antifreeze by wearing hand protection.

ENGINE COOLING SYSTEM

To protect the engine cooling system against corrosion it is essential that the engine coolant contains suitable additives which will give the necessary protection.

Caution: untreated water is not suitable.

WATER QUALITY

The water that is mixed with the additive must have the following characteristics:

Chloride less than 80 PPMV (parts per million by volume)

Sulphates less than 80 PPMV

Total hardness less than 200 PPMV pH of water between 7 to 7.5 (i.e. neutral to slightly alkaline)

ADDITIVES TO WATER

Due to the complexity. of the cooling system it is necessary to use an additive that contains a balanced package .of corrosion inhibitors.

To achieve the required solution a 50/50 mix of Shell Safe Premium anti-freeze with water should be used at all times, even in areas where frost is unlikely.

This mixture will give frost protection down to -35℃. In areas where Shell anti-freeze is unobtainable contact Perkins Engines (Stafford) Ltd for advice.

Under no circumstances should an additive containing nitrites, borate, phosphates, chromates, nitrates or silicates  be used, as these materials are not compatible with the materials used in the cooling system.

When mixing the anti-freeze with the water always follow the manufacturer's recommendation which is to add the anti-freeze to water and mix thoroughly before adding the mixture to the engine cooling system.

Mixing water to the anti-freeze can lead to the formation of gel in the mixture, due to over concentration, and this can lead to blockage of water passages and subsequent loss of water flow causing overheating.

MAINTENANCE OF COOLANT

The water/anti-freeze mixture should be replaced in operating engines at least once a year.

It is essential to maintain the coolant at the correct alkalinity level i.e. the pH should not increase above 7.5. A hydrometer only shows the proportion of ethylene glycol. This is not a measure of protection against corrosion.

WARNING!! Failure to follow the above recommendations may result in engine damage and will invalidate the engine warranty.

FUEL SPECIFICATION

Fuel should be wholly hydrocarbon oil derived from petroleum, with which small quantities of additives may be incorporated for the improvement of ignition or other characteristics and should conform to British Standard Specification 2869. Ct.ass Al or A2.

If fuels other than the above classes are considered, the operator must consult Perkins Engines (Stafford) Limited, and ensure that a suitable grade of lubricating oil is used.

++This limit is set in accordance with the legislative requirements for gas oil of the 'Council Directive (75/716/EEC of the European Economic Community) on the approximation of the laws of Member States relating to the sulphur content of certain liquid fuels'.