WÄRTSILÄ WARTSILA32, Product Manual, Page: 103 / 254

7. Lubricating Oil System
7.1 Lubricating oil requirements
7.1.1 Engine lubricating oil
The lubricating oil must be of viscosity class SAE 40 and have a viscosity index (VI) of minimum
95. The lubricating oil alkalinity (BN) is tied to the fuel grade, as shown in the table below. BN
is an abbreviation of Base Number. The value indicates milligrams KOH per gram of oil.
Table 7-1 Fuel standards and lubricating oil requirements
Lubricating oil BN Fuel standard Category
10...30
GRADE NO. 1-D, 2-D, 4-D
DMX, DMA, DMB
DX, DA, DB
ISO-F-DMX, DMB ASTM D 975-01,
BS MA 100: 1996
CIMAC 2003
ISO8217: 2012(E)
A
15...30
GRADE NO. 1-D, 2-D, 4-D
DMX, DMA, DMB
DX, DA, DB
ISO-F-DMX - DMB ASTM D 975-01
BS MA 100: 1996
CIMAC 2003
ISO 8217: 2012(E)
B
30...55
GRADE NO. 4-D
GRADE NO. 5-6
DMC, RMA10-RMK55
DC, A30-K700
RMA10-RMK 700 ASTM D 975-01,
ASTM D 396-04,
BS MA 100: 1996
CIMAC 2003
ISO 8217: 2012(E)
C
30...55 CRUDE OIL (CRO) D
10...20 LIQUID BIO FUEL (LBF) F
BN 50-55 lubricants are to be selected in the first place for operation on HFO. BN 40 lubricants
can also be used with HFO provided that the sulphur content of the fuel is relatively low, and
the BN remains above the condemning limit for acceptable oil change intervals. BN 30
lubricating oils should be used together with HFO only in special cases; for example in SCR
(Selective Catalyctic Reduction) installations, if better total economy can be achieved despite
shorter oil change intervals. Lower BN may have a positive influence on the lifetime of the
SCR catalyst.
Crude oils with low sulphur content may permit the use of BN 30 lubricating oils. It is however
not unusual that crude oils contain other acidic compounds, which requires a high BN oil
although the sulphur content of the fuel is low.
It is not harmful to the engine to use a higher BN than recommended for the fuel grade.
Different oil brands may not be blended, unless it is approved by the oil suppliers. Blending
of different oils must also be approved by Wärtsilä, if the engine still under warranty.
An updated list of approved lubricating oils is supplied for every installation.
7.1.2 Oil in speed governor or actuator
An oil of viscosity class SAE 30 or SAE 40 is acceptable in normal operating conditions. Usually
the same oil as in the engine can be used. At low ambient temperatures it may be necessary
to use a multigrade oil (e.g. SAE 5W-40) to ensure proper operation during start-up with cold
oil.
7.1.3 Oil in turning device
It is recommended to use EP-gear oils, viscosity 400-500 cSt at 40°C = ISO VG 460.
Wärtsilä 32 Product Guide - a21 - 7 September 2016 7-1
7. Lubricating Oil System Wärtsilä 32 Product Guide