Table of Contents
Advertisement
Manual
F 240
4. Testing engine
lubricating oil
5. No- -Go criteria for
engine
lubricating oil
No Go criteria
Ver. 01
LUBRICATING OIL SYSTEM
6B
LUBRICATING OIL REQUIREMENTS
When testing the quality of the lubricating oil for the engine the specifications and
instructions of the oil supplier have to be observed.
Under normal operating conditions samples of lubricating oil should be taken in
accordance with the maintenance schedule. On the basis of the results of the tests to
be carried out by the oil supplier it can be determined whether the lubricating oil is
suitable for further use. It is also recommended to subject these samples to a special
analysis in order to watch the wear development of various engine components. It is
a good habit to test the oil for the presence of water every week.
Beside the lubrication function the engine lubrication oil must also prevent oxidation
products coming from fuel and lubricating oil depositing on engine parts and keep
these oxidation products well dispersed. The oxidation products are only partly
removed from the lubricating oil by the lubricating oil filter. This ultimately requires
replacement of the lubricating oil. The replacement intervals depend on the operating
conditions and the efficiency of the lubricating oil treatment and the quantity of oil in
circulation.
A sudden increase in sludge or carbon deposits in the crankcase or camshaft housing
indicates that the quality of the lubricating oil has deteriorated.
Before one of the criteria below has been reached the lubricating oil can be brought
back to normal condition in some cases.
With shorter intervals between cleaning of the separator it is possible to intensify
separation and thus decrease water and insolubles to within specification. Always
consult the lubricating oil supplier.
--
rate of change of viscosity
--
flash point
--
pentane insolubles
--
toluene insolubles
--
pentane insolubles minus toluene insolubles
--
water content
--
TBN
--
Spectral analysis.
If the results of the lubricating oil analysis show that the no--go criteria are exceeded
it is recommended to condemn the lubricating oil. The specifications of the oil supplier
are to be adhered to.
--20/+20% ;
below 180
above 2.5% ;
above 2 % ;
above 0.5% ;
above 0.2 % ;
below 60% of original value.
--o--o--o--o--o--
0
C ;
6 - - 4
Advertisement
Table of Contents
