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Personal injury or death can result if two persons are not used in the following procedure. |
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Personal injury can result if the machine moves while testing. If the machine begins to move during test, reduce the engine speed immediately and engage the parking brake. |
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Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To prevent possible injury, perform the procedure that follows before testing and adjusting the brake system. |
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| NOTICE |
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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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products. Dispose of all fluids according to local regulations and mandates. |
Specification
| Service Brake System Pressure - Test (Front wheels) | ||
| Date | Equipment ID Code | |
| Description | Specification | Actual |
| Front Brakes | 5862 + 517 - 345 kPa (850 +75 - 50 psi) | |
| Maximum Pressure 5 seconds after brakes released | 140 kPa (20 psi) |
|
| Service Brake System Pressure - Test (Rear Wheels) | ||
| Date | Equipment ID Code | |
| Description | Specification | Actual |
| Front Brakes | 5862 + 517 - 345 kPa (850 +75 - 50 psi) |
|
| Maximum Pressure 5 seconds after brakes released | 140 kPa (20 psi) |
|
Introduction
This procedure will check the service brake pressure at the front and rear wheels.
Required Tools
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| Illustration 1 | g01623868 |
Tooling (B) | |
| Tool | Item | Part Number | Description | Qty |
|---|---|---|---|---|
| B | 198-4240 | Digital Pressure Indicator Gp | ||
| B1 | 198-4234 | Digital Indicator | 1 | |
| B2 | 251-9600 | Pressure Sensor Gp (0 to 68,900 kPa (0 to 10,000 psi)) | 2 | |
| B3 | 198-4236 | Adapter Cable As | 2 | |
Machine Preparation
- Move the machine to a smooth, horizontal location. Move the machine away from other operating machines and away from personnel. Place the transmission direction control switch in the NEUTRAL position. Engage the parking brake. Lower the bowl to the ground. Stop the engine and put chocks in front of the wheels and behind the wheels.
- Use a suitable lifting device to support the section of the belly pan that has an access port. Then remove the belly pan and move the belly pan out of the way.
Note: The weight of the belly pan is 98.8 kgs (218 lbs).
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| Illustration 2 | g02640476 |
View of the portion of the belly pan that has the access port | |
- Connect (B) to (1) in order to check the front service brakes.
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| Illustration 3 | g03333990 |
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| Illustration 4 | g02627863 |
Distant up view of the pressure tap for the front service brakes | |
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| Illustration 5 | g03866895 |
Close up view of the pressure tap for the front service brakes | |
- Connect (B) to (2) in order to check the rear service brakes.
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| Illustration 6 | g02635077 |
Rear of scraper near ejector cylinder. | |
Test Procedure for the Front Wheels
- Start the engine and allow the engine to warm up to normal operating temperature. Run the engine at low idle.
- Depress the service brake pedal and hold the brake pedal in the fully applied position. The brake lamps should be on when the service brake pedal is in the FULLY APPLIED position.
- The brake pressure for the front axle should check 5862 + 517 - 345 kPa (850 + 75 - 50 psi).
- Release the service brake pedal. The front brake pressure shall be a maximum of 140 kPa (20 psi) within 5 seconds after the service brake pedal has been released.
- Remove all test equipment. and reinstall the dust covers.
- Reinstall the belly pan.
Test Procedure for the Rear Wheels
- Start the engine and allow the engine to warm up to normal operating temperature. Run the engine at low idle.
- Depress the service brake pedal and hold the brake pedal in the fully applied position. The brake lamps should be on when the service brake pedal is in the FULLY APPLIED position.
- The brake pressure for the rear axle should check 5690 + 517 - 345 kPa (825 + 75 - 50 psi).
- Release the service brake pedal. The rear brake pressure shall both be a maximum of 140 kPa (20 psi) within 5 seconds after the service brake pedal has been released.
- Remove all test equipment and install dust covers.
If the Service Brake System Pressure Test is not to Standard
- Check accumulator pre-charges by referring to Test and Adjust, "Brake Accumulator (Service) - Test and Charge" in this manual.
- Purge brakes thoroughly. Refer to Test and Adjust, "Parking Brake Purge Procedure" in this manual.
- Check the accumulator pressures. Refer to the Test and Adjust, "Test and Adjust- Brake Accumulator Charging Valve-Test"
- Inspect brake pedal located in the cab.