- Articulated Truck:
- D350E Series II (PIN: 2XW1-UP)
- D400E Series II (PIN: 8PS1-UP)
- D400E Series II Ejector (PIN: APF1-UP)
An improved procedure has been developed for checking the wear of service brakes on the listed Articulated Trucks. The following procedure can be carried out for checking the service brakes on the front and center axles.
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Personal injury or death can result from sudden machine movement. Sudden movement of the machine or release of oil pressure can cause injury to persons on or near the machine. To help prevent possible injury or death, refer to the information in Testing and Adjusting, "Machine Preparation for Troubleshooting". |
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Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin. |
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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, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates. |
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| Illustration 1 | g00670331 |
Plug Gauge | |
Use the 160-1726 Plug Gauge to measure the brake wear at the service brakes.
Procedure
Note: This procedure must be carried out with a cold engine.
- Start the engine and run the engine at low idle rpm until the accumulators for the service brakes are fully charged. Run the engine for approximately two minutes.
- Stop the engine. Move the parking and secondary brake control to the ENGAGED position.
- Remove plug (1) .
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| Illustration 2 | g00670328 |
Location of the plug (1) Plug | |
- Install the 160-1726 Plug Gauge .
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| Illustration 3 | g00670329 |
- Allow the operator to press and hold the pedal for the service brake. The service brakes will engage and the brake discs will be compressed.
- Push the rod through the plug gauge until contact is made with the brake piston.
- Use a suitable tool to measure the distance between the end of the rod and the face of the plug gauge. Record the measurement. Refer to Illustration 4.
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| Illustration 4 | g00670391 |
- The operator can now release the pedal for the service brake.
- Remove the plug gauge.
- Check the O-ring seal for plug (1). If the O-ring seal is damaged, replace the O-ring seal.
- Install plug (1) .
- Use Table 1 to determine the amount of brake wear that has taken place.
- Perform steps 1 to 12 at each brake group.
| Measured Dimension | Wear in Percentage |
16.8 mm (0.661 inch) |
0% |
15.68 mm (0.617 inch) |
20% |
14.56 mm (0.573 inch) |
40% |
13.45 mm (0.530 inch) |
60% |
12.33 mm (0.485 inch) |
80% |
11.21 mm (0.441 inch) |
100% |
The dimensions in Table 1 are nominal figures. These dimensions can vary due to manufacturing tolerances. The variation is ± 1.124 mm (± 0.0443 inch) when the friction discs are new. An accurate indication of brake wear can be achieved by recording measurements from each location when the machine is new or when new friction discs have been installed. These records can be used as a comparison for future measurements.
When a second measurement is taken, the difference should be subtracted from the previous recorded measurement. The result will indicate the amount of brake wear that has taken place.
Note: The total maximum wear for the 11 friction discs which make up each brake group is 5.588 mm (0.2200 inch). If the difference between the new measurement that was recorded and the used measurement is greater than 5.588 mm (0.2200 inch) the friction discs should be replaced.