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. |
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. |
Note: Press the horn to alert personnel in the area.
Note: Test the brakes on a dry, level surface. Make sure that the area around the machine is clear. Move the machine away from other operating machines and away from personnel.
Note: If the machine is on stands, place the steering frame lock in the LOCKED position. Clear the area around the wheels in order to allow the wheels to rotate.
Note: Engage the parking brake.
Required Tools     | ||
Part Number     | Description     | Qty     |
198-4240     | Digital Pressure Indicator     | 1     |
2G-5298     | Wire     | 1     |
- Remove the access panel on the lower right side of the machine by the door.
- Disable the neutralizer by removing the parking brake alarm relay and the parking brake relay.
Illustration 1 | g00488500 |
Location of the parking brake relay and parking brake alarm relay (1) Parking brake alarm relay (2) Parking brake relay |
- Insert 2G-5298 Wire Assembly into the relay panel at locations F3 and D5.
Note: This will supply the power to the directional control lever. The limit switch to the parking brake control lever will be ignored.
Illustration 2 | g00488501 |
Jumper Wire Location (3) Location F3 (4) Location D5 |
- Rotate stem (5) on shutoff valve (6) counterclockwise in order to block the hydraulic oil to the inching valve.
Illustration 3 | g00477269 |
Location of the Shutoff Valve (5) Stem (6) Shutoff valve |
- Install 198-4240 Digital Pressure Indicator to the pressure tap for the high pressure oil of the drive loop (7) .
Illustration 4 | g01052434 |
Pressure Tap Location for the High Pressure Oil of the Drive Loop (7) Pressure tap for the high pressure oil of the drive loop. |
Note: Remove the access panel that is under the battery.
- Purge the service brakes of air. Refer to Systems Operation and Testing and Adjusting, "Brake System Air- Purge".
- Install 198-4240 Digital Pressure Indicator to the pressure tap for service brake (8) that is on the axle assembly.
Illustration 5 | g01047159 |
Location of Pressure Tap on Front Axle Housing (8) Pressure tap for the service brake. |
- Secure the digital pressure indicator so that the digital pressure indicator can be viewed during the test. Do NOT hold the digital pressure indicator.
- Sit in the seat and fasten the seat belt.
- Start the engine and allow the machine to reach normal operating temperature.
- With the machine at low idle, raise the empty bucket or attachment slightly. Push down and hold either brake pedal in order to apply the service brakes. Disengage the parking brake.
- Move the directional control lever to the FORWARD direction. If the machine is equipped with a speed select switch, press the speed select switch to FAST. If the machine is equipped with a creeper speed control, move the lever for the creeper speed control all the way forward into the FAST detent.
NOTICE |
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Do not drive through the service brake more than 15 seconds. |
- Apply the service brake until a pressure of 3800 ± 450 kPa (550 ± 65 psi) is indicated on the pressure gauge to pressure tap (8) .
- Slowly increase the engine speed until the machine moves. Hold the service brake pedal and the accelerator pedal in that position.
- At the same time, check the high pressure oil of the drive loop. For the 914G machines, the pressure gauge should indicate 25250 ± 5000 kPa (3660 ± 725 psi). For the IT14G machines, the pressure gauge should indicate 22500 ± 5000 kPa (3260 ± 725 psi).
- Move the directional control lever to the NEUTRAL position.
- Purge the service brakes of air. Ensure that the inching valve is fully closed.
NOTICE |
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If the high pressure oil of the drive loop is not within specification, inspect the service brake components for wear or damage. Repair or replace the worn or damaged service brake components as required and repeat this testing procedure before returning the machine to service. |
- If the pressure is not within the specification, replace the brake valve.
- If the pressure is within the specification, then remove all of the test equipment.
- Rotate stem (5) on shutoff valve (6) clockwise in order to open the hydraulic oil to the inching valve.
- Remove the 2G-5298 Wire Assembly. Install relays (1) and (2) and install the relay panel.