Perkins 1103D Operation And Maintenance Manual page 36

36
Maintenance Section
Fluid Recommendations
Three new engine tests were developed for the API
CH-4 oil. The first test specifically evaluates deposits
on pistons for engines with the two-piece steel piston.
This test (piston deposit) also measures the control
of oil consumption. A second test is conducted with
moderate oil soot. The second test measures the
following criteria: wear of piston rings, wear of
cylinder liners and resistance to corrosion. A third
new test measures the following characteristics with
high levels of soot in the oil: wear of the valve train,
resistance of the oil in plugging the oil filter and
control of sludge.
In addition to the new tests, API CH-4 oils have
tougher limits for viscosity control in applications that
generate high soot. The oils also have improved
oxidation resistance. API CH-4 oils must pass an
additional test (piston deposit) for engines that use
aluminum pistons (single piece). Oil performance is
also established for engines that operate in areas
with high sulfur diesel fuel.
All of these improvements allow the API CH-4 oil to
achieve optimum oil change intervals. API CH-4 oils
are recommended for use in extended oil change
intervals. API CH-4 oils are recommended for
conditions that demand a premium oil. Your Perkins
dealer or your Perkins distributor has specific
guidelines for optimizing oil change intervals.
Some commercial oils that meet the API
classifications may require reduced oil change
intervals. To determine the oil change interval,
closely monitor the condition of the oil and perform a
wear metal analysis.
NOTICE
Failure to follow these oil recommendations can
cause shortened engine service life due to deposits
and/or excessive wear.
Total Base Number (TBN) and Fuel Sulfur
Levels for Direct Injection (DI) Diesel
Engines
The Total Base Number (TBN) for an oil depends on
the fuel sulfur level. For direct injection engines that
use distillate fuel, the minimum TBN of the new oil
must be 10 times the fuel sulfur level. The TBN is
defined by "ASTM D2896". The minimum TBN of the
oil is 5 regardless of fuel sulfur level. Illustration 20
demonstrates the TBN.
Illustration 20
(Y) TBN by "ASTM D2896"
(X) Percentage of fuel sulfur by weight
(1) TBN of new oil
(2) Change the oil when the TBN deteriorates to 50 percent of the
original TBN.
Use the following guidelines for fuel sulfur levels that
exceed 1.5 percent:
• Choose an oil with the highest TBN that meets
one of these classifications: EMA DHD-1 and API
CH-4.
• Reduce the oil change interval. Base the oil
change interval on the oil analysis. Ensure that the
oil analysis includes the condition of the oil and a
wear metal analysis.
Excessive piston deposits can be produced by an oil
with a high TBN. These deposits can lead to a loss of
control of the oil consumption and to the polishing of
the cylinder bore.
NOTICE
Operating Direct Injection (DI) diesel engines with
fuel sulphur levels over 0.5 percent will require short-
ened oil change intervals in order to help maintain ad-
equate wear protection.
Table 6
Percentage of Sulfur in the
fuel
Lower than 0.5
0.5 to 1.0
Greater than 1.0
Lubricant Viscosity Recommendations
for Direct Injection (DI) Diesel Engines
The correct SAE viscosity grade of oil is determined
by the minimum ambient temperature during cold
engine start-up, and the maximum ambient
temperature during engine operation.
SEBU8352-02
g00799818
Oil change interval
Normal
0.75 of normal
0.50 of normal