WÄRTSILÄ PAAE051728, Инструкция по эксплуатации

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Viscosity. Should not decrease by more than 20% and not rise by
more than 25% above the guidance value at 100 °C.
Should not decrease by more than 25 % and not rise by more than
45% above the guidance value at 40 °C.
Flash point. Should not fall by more than 50 °C below the guidance
value. Min. permissible flash point 190 °C (open cup) and 170 °C
(closed cup) . At 150 °C risk of crankcase explosion.
Water content. Should not exceed 0.3%. A value higher than 0.3%
can not be accepted for longer periods, but measures must be
taken; either centrifuging or oil change.
BN (Base Number).
·
Fuel category A and B:
The minimum allowable BN value of a used oil is 50% of the
nominal value of a new oil.
·
Fuel categories C and D:
The minimum allowable value of used oil is BN 20.
Insolubles. The quantity allowed depends on various factors. The oil
supplier’s recommendations should be followed. However, an n-Pen-
tane insoluble value above 1.5% calls for attention. A value higher
than 2% cannot be accepted for longer periods.
In general it can be said that the changes in the analyses give a
better basis of estimation than the absolute values.
Fast and great changes may indicate abnormal operation of the
engine or of a system.
c) Compensate for oil consumption by adding max. 10% new oil at a
time. Adding larger quantities can disturb the balance of the used
oil causing, for example, precipitation of insolubles. Measure and
record the quantity added.
Attention to the lubricating oil consumption may give valuable
information about the engine condition.
A continuous increase may indicate that piston rings, pistons and
cylinder liners are getting worn, and a sudden increase motivates
pulling the pistons, if no other reason is found.
d) Guidance values for oil change intervals are to be found in chap-
ter 04. Intervals between changes are influenced by system size (oil
volume), operating conditions, fuel quality, centrifuging efficiency
and total oil consumption. Efficient centrifuging and large systems
(dry sump operation) generally allow for long intervals between
changes. It is recommended to follow up that the BN value of the
lubricating oil keeps within engine manufacturer’s limits during the
whole oil change interval.
When changing oil the following procedure is recommended:
1 Empty oil system while oil is still hot. Be sure that oil filters and
coolers are also emptied.
2 Clean oil spaces, including filters and camshaft compartment.
Insert new filter cartridges.
3 Fill a small quantity of new oil in the oil sump and circulate with
the pre-lubricating pump. Drain!
200549-01 Fuel, Lubricating Oil, Cooling Water
W20/W32/W46, W46F, 32, 32LN 02 - 15