 |
Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak. |
 |
|
Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand. |
|
| NOTICE |
|---|
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates. |
Introduction
The following tests are used to obtain a scheduled oil sample of the hydraulic system.
Required Tools
| Required Tools | ||||
|---|---|---|---|---|
| Tooling | Item | Part Number |
Description | Qty |
| A | A1 | 169-8373 | Fluid Sampling Bottle | 1 |
Testing Procedure
If the oil becomes contaminated, premature component failure could result. Contaminated oil can also contribute to overheating.
A scheduled oil sample can be taken from the oil bypass valve which is located at callout (1) or from the oil cooler manifold which is located at callout (4) . The pressure measured at callout (1) is the same as the pressure coming out of the transmission pump and going to the transmission oil filter. The pressure measured at callout (4) is the same as the pressure coming out of the torque converter and going to the transmission oil cooler. To take a scheduled oil sample use the required tools and testing procedure described below.
Note: If insufficient oil pressure is measured anywhere in the transmission hydraulic control system, test the pressure of the oil at the oil filter bypass valve. The pressure that is measured at the oil bypass valve will be the same pressure that is measured at the transmission hydraulic control relief valve.
 | |
| Illustration 1 | g01331818 |
 | |
| Illustration 2 | g01654816 |
Use the following procedure to determine the contamination of the oil in the hydraulic system.
- Start the engine. Warm up the oil until the oil reaches 47 °C (116 °F).
- Ensure that the transmission control is in the NEUTRAL position and place the throttle in the LOW IDLE position.
- Remove cap (2) . Obtain an oil sample from SOS tap (3) using tooling (A) .
- Stop the engine.
- Check the hydraulic filter element for foreign materials.
- Replace the hydraulic filter element.
- Bronze colored particles give an indication of sleeve bearing failure.
- Shiny steel particles give an indication of bearing or gear failure.
- Rubber particles indicate a seal failure or a hose failure.
- Aluminum particles give an indication of converter wheel failure.
- Plastic particles give an indication of thrust washer or rotating seal failure.
Note: If any of these particles are found in the hydraulic filter element, all components of the hydraulic oil system must be cleaned. Do not use any damaged parts. Any damaged parts must be removed, and new parts must be installed.
Refer to Caterpillar Operation and Mainenance Manual, SEBU6250, "Machine Fluids Recommendations" for more information about obtaining a proper SOS oil sample, SOS Oil Analysis guidelines, oil sampling intervals, contamination control, and component life cycle management.