- Wear Analysis
- Oil condition
- Additional tests
The wear analysis monitors metal particles, some oil additives, and some contaminants.
Oil condition uses infrared (IR) analysis to evaluate the chemistry of the oil. Infrared analysis is also used to detect certain types of contamination.
Additional tests are used to measure contamination levels from water, fuel, or coolant. Oil viscosity and corrosion protection can be evaluated, as needed.
These three types of analysis are used to monitor the condition of your engine and potential problems can be detected. A properly administered S·O·S Oil Analysis program will reduce repair costs and the program will lessen the impact of downtime.
The S·O·S Oil Analysis program uses a wide range of tests to determine the condition of the oil and the condition of the lubricated compartment.
Guidelines that are based on experience and a correlation to failures have been established for these tests. See the following chart for the guidelines. Exceeding one or more of these guidelines could indicate serious fluid degradation or a pending component failure. A trained person at your Caterpillar dealership should make the final analysis.
Note: Cooling system problems will also reduce the life of engines. The combination of S·O·S Coolant Analysis and S·O·S Oil Analysis provide a complete, accurate method for monitoring the health of all Caterpillar engines. Refer to the S·O·S Coolant Analysis information in this publication. A properly administered S·O·S Services program will reduce repair costs. The program will also lessen the impact of downtime.
| S·O·S Oil Analysis Guidelines | |
|---|---|
| Test Parameter | Guideline |
| Oxidation | (1) |
| Soot | (1) |
| Sulfation | (1) |
| Wear Metals | Trend Analysis and Cat Wear Table (1) norms |
| Water | 0.5% maximum |
| Glycol | 0% |
| Fuel Dilution | 4% maximum |
| Viscosity - engines by "ASTM D445" measured at 100° C (212° F) |
+/-3 centistoke (cSt) change from new oil viscosity. |
| Total Base Number (TBN) by "ASTM D2896" | 50% of new oil TBN |
| Total Acid Number (TAN) by "ASTM D664" | 2.0 greater than new oil TAN or 3.0 maximum |
| ( 1 ) | Acceptable values for these parameters are proprietary to the S·O·S Oil Analysis program. |
Consult your Caterpillar dealer for complete information and assistance about the S·O·S Oil Analysis program.
Obtaining S·O·S Oil Samples
Before you obtain an S·O·S oil sample, operate the engine until the oil is warm and the oil is well circulated. Then obtain the S·O·S oil sample.
In order to obtain a good oil sample, do not take the oil sample from the drain stream. The drain stream method can allow a stream of dirty oil from the bottom of the compartment to contaminate the sample. Likewise, never dip an oil sample from an oil container or pour a sample from a used filter.
| NOTICE |
|---|
Always use a designated pump for oil sampling, and use a separate designated pump for coolant sampling. Using the same pump for both types of samples may contaminate the samples that are being drawn. This contaminate may cause a false analysis and an incorrect interpretation that could lead to concerns by both dealers and customers. |
There are two ways to obtain S·O·S oil samples. The following methods are listed in the order that is preferred:
- Use an in-line sampling valve for pressurized oil systems.
- Use a sampling gun that is inserted into the sump.
Use of the in-line sampling valve is the preferred method. This method provides samples that are less likely to be contaminated. Whenever you obtain the samples, obtain the samples from the same point. This makes the samples more representative of the oil that is in the system.
In order to obtain an oil sample from the engine compartment, it may be necessary to increase the engine's speed. Normally, the oil sample is taken at low idle. If the flow rate is too low, increase engine speed to high idle in order to obtain the oil sample.
Refer to the Operation and Maintenance Manual, "Maintenance Interval Schedule" for the proper interval.
Sampling Interval
Take the oil samples as close as possible to the standard intervals. In order to receive the full value from S·O·S oil analysis, you must establish a consistent trend of data. In order to establish a pertinent history of data, perform consistent oil samplings that are evenly spaced.
| Compartment | Engine |
| Recommended Sampling Interval | 24140 kilometers (15000 miles) (1) |
| Sampling Valve | Yes |
| Oil Type | DEO |
| Recommended Oil Change Interval | (2) |
| ( 1 ) | Under certain conditions, the Caterpillar dealer or the Operation and Maintenance Manual may allow a longer interval between oil samplings. |
| ( 2 ) | Consult the Operation and Maintenance Manual that came with your engine for the recommended oil change intervals. |
Consult your Caterpillar dealer for complete information and assistance in establishing an S·O·S program for your equipment.
More Frequent S·O·S Sampling Improves Life Cycle Management
Traditionally, the suggested S·O·S sampling intervals have been at each oil change. However in severe applications, more frequent oil sampling is recommended. If the engine is operated under a high load and/or high temperature condition, sample at every 250 hours of operation.
Application
Studies have revealed that obtaining oil samples at every 24140 kilometers (15000 miles) is too long a time interval in some applications in order to predict potential failure modes. A sampling interval at every 16093 kilometers (10000 miles) provides more data between oil change intervals. More data increases the chance for detecting a potential failure.
Determining Optimum Oil Change Intervals
Sampling the compartments at every 16093 kilometers (10000 miles) provides information for oil condition and for oil performance. This information is used to determine the optimum usable life of a particular oil. Also, more points of data will allow closer monitoring of component wear rates. Close monitoring also allows you to obtain the maximum use of the oil. For detailed information on extending oil change intervals, please contact your Caterpillar dealer.
Optimizing the Component Life Cycle
An increase in the number of oil samples provides a better definition of the trends in data between oil change intervals. More oil samples will allow you to closely monitor wear patterns of components. This action will ensure that the full life of the components are achieved.