SLACK ADJUSTER GP 1692903 - Caterpillar

The Caterpillar Scheduled Oil Sampling Program was developed to help Caterpillar users realize the highest possible value from their equipment by minimizing repair costs and maximizing availability. The S.O.S program is a series of diagnostic tests which analyze the lubricating oils used in the equipment. By analyzing the oils, problems may be identified early, before an extensive component failure occurs. This reduces both repair cost and downtime.
An S.O.S program must be coupled with a wide range of repair options so that when a problem is identified, an appropriately matched repair plan is available. When S.O.S is used to detect a repair indicator in a repair option program, the dealer can offer the user a more complete service to minimize repair cost and downtime. S.O.S can also measure the effectiveness of the user's maintenance program.
The purpose of this article is to review the specific diagnostic tests in the S.O.S program, summarizing the capabilities, limitations, and relationship of each test. Oil analysis tests not included in the S.O.S program will also be discussed.
Wear Analysis
Wear analysis is the original diagnostic test which began the S.O.S program. It is still the foundation of the program. Wear analysis monitors the component's (i.e., engine, transmission, hydraulic systems, final drives, etc.) wear rates by measuring the wear elements and contaminants found in the used oil. By monitoring the used oil, component wear trends can be determined, and many failures can be identified when wear elements and/or contaminants significantly exceed past trends. In many cases the source of abnormal wear may be pinpointed (i.e. high lead and aluminum readings may indicate a pending bearing failure).
The failures which can be detected are those caused by component wear and gradual dirt contamination. Wear analysis is not able to predict failures due to component fatigue, sudden loss of lubrication, or sudden ingestion of a large amount of dirt because these situations occur too rapidly to predict.
The atomic absorption (AA) spectrophotometer has been the only equipment recommended. This spectrophotometer can accurately measure the microscopic particles (i.e., less than three microns) suspended in the lubricating oil. These particles are small enough to pass through the filter. This spectrophotometer cannot measure particles which are large enough to be visible.
The Inductively Coupled Plasma (ICP) and Direct Coupled Plasma (DCP) also are capable of performing wear analysis. In the past, this type of spectrophotometer has not been recommended for dealer use because the equipment is considerably more expensive and it was uncertain whether the wear limits developed for the atomic absorption analysis would be applicable. Recent development work has proved that the existing atomic absorption wear limits can be used for some atomic emission analysis machines. For high volume labs, the atomic emission spectrophotometer may be the best choice because it is much faster. Before an equipment decision is made, a complete financial analysis is recommended. (ICP and DCP equipment can cost 30-40% more than AA equipment, but also provides a 30-40% reduction in analysis time.)
Chemical And Physical Tests
Chemical and physical tests are used