3176C Engine Caterpillar

Caterpillar recommends the use of the S·O·S oil analysis program in order to monitor the condition and the maintenance requirements of the equipment. The S·O·S oil analysis program will complement the preventive maintenance program.

The S·O·S oil analysis is a diagnostic tool that is used to determine oil performance and component wear rates. Contamination can be identified and measured through the use of the S·O·S oil analysis. The S·O·S oil analysis is composed of four basic tests:

• The Wear Rate Analysis monitors wear by detecting, identifying and assessing the amount and the type of engine wear metal that is in the oil. The increase in the rate of engine wear metal in the oil is as important as the quantity of engine wear metal in the oil. For this reason, regular sampling at specified intervals is necessary in order to establish wear rates. Intermittent sampling does not allow wear rate trend lines to be established. Engine wear metals in the oil sample are compared to established Caterpillar norms in order to determine acceptability.

• The Oil Cleanliness Analysis uses a Particle Count test for nonengine oil. This analysis detects both metallic debris and nonmetallic debris (friction disc material) that is generated by wear as well as dirt from outside sources. This information and the Wear Rate Analysis permits a comprehensive evaluation of the hydraulic systems and the power train systems. This combination can detect potential failures that are not identified by the Wear Rate Analysis alone.

• Tests are conducted in order to detect contamination of the oil by water, glycol or fuel.

• The Oil Condition Analysis determines the loss of the oil's lubricating properties. An infrared analysis is used to compare the properties of new oil to the properties of the used oil sample. This analysis allows technicians to determine the amount of deterioration of the oil during use. This analysis also allows technicians to verify the performance of the oil according to the specification during the entire oil change interval.

The test results of the oil samples will then be used as a basis for determining the oil change interval for the engine. The results of the S·O·S oil analysis may allow the engine to operate longer between oil changes without the risk of engine damage.

Refer to Special Publication, PEDP7036 for more information.

Table 1

Interval for S·O·S Oil Analysis
Compartment	Interval
Engine crankcase	Every 300 Service Hours

Obtain the oil sample when the oil is warm and well mixed in order to ensure that the sample is representative of the oil in the engine crankcase.

Consult your Caterpillar dealer for complete information and assistance about the program.