The Caterpillar Scheduled Oil Sampling Program was developed in order to help the users of Caterpillar equipment to realize the equipment's full value. The S·O·S program will help the user in minimizing repair costs and maximizing availability. The S·O·S program is a series of diagnostic tests which analyze used lubricating oils from the oil wetted compartments of the equipment. By analyzing the used oils, problems may be identified early before extensive repair cost and downtime are incurred.
The S·O·S program is coupled with a wide range of repair options. When a problem is identified, an appropriate matched repair plan is available. The matched repair plan offers the user a more complete service in order to help minimize repair costs and scheduled downtime. The S·O·S program can also measure the effectiveness of the user's maintenance program.
Obtaining S·O·S Oil Samples
Before you obtain an S·O·S oil sample, operate the machine 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.
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-line sampling valves cannot be used on nonpressurized oil systems such as differentials and final drives. Use of the sampling gun is the preferred method for nonpressurized oil systems.
Refer to the Operation and Maintenance Manual, "Maintenance Interval Schedule" for the proper interval.
The S·O·S oil analysis is composed of four basic tests:
- Wear metal analysis
- Infrared analysis for oil condition
- Tests for contamination of the oil by fuel, by water, and/or by antifreeze
- Particle Count for hydraulics, transmissions and other gear compartments
Consult your Caterpillar Dealer for complete information and assistance about the S·O·S oil analysis program.
S·O·S Interval and Location of Sampling Valve for the Final Drive
The S·O·S interval for the final drive is 500 hours.
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.
Refer to Special Publication, SEBU6250, "Caterpillar Machine Fluid Recommendations" for detailed information concerning S·O·S oil analysis.
Consult your Caterpillar dealer for complete information and assistance in establishing an S·O·S program for your equipment.
Final Drive Oil Sample
Type "A" Final Drive
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| Illustration 1 | g00847418 |
(1) Oil drain plug (2) Oil level plug (3) Oil filler plug | |
- Position the final drive so that oil drain plug (1) is at the bottom.
- Remove oil level plug (2) .
- Obtain a sample of the final drive oil through the hole for the oil level plug.
- Install oil level plug (2) .
Type "B" Final Drive
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| Illustration 2 | g00538194 |
(1) Oil drain plug (2) Oil level plug | |
- Position the final drive so that oil drain plug (1) is at the bottom.
- Remove oil level plug (2) .
- Obtain a sample of the final drive oil through the hole for the oil level plug.
- Install oil level plug (2) .