- Motor Grader:
- 143H (S/N: 5AK1-UP)
- 163H (S/N: 1AL1-UP)
- 143H (S/N: APN1-315)
- 163H (S/N: ARL1-290)
- 163H (S/N: 1AL1-UP)
Introduction
A pressure sensor that is more compact is now available. The more compact 221-3416 Pressure Sensor can be used as a replacement for the 124-4672 Pressure Sensor .
This Special Instruction contains information and procedures that can be referenced when the 124-4672 Pressure Sensor for the all wheel drive system is updated. The update for the pressure sensor will apply to Tier I Motor Graders and some Tier II Motor Graders. The 221-3416 Pressure Sensor is original equipment on most Tier II Motor Graders.
Read the entire special instruction. Understand the information before you perform any procedures. Understand the information before you order any parts.
Procedure to Update the All Wheel Drive Pressure Sensor
Refer to Product Safety, SENR7733, "Important Safety Information" before performing this procedure.
| Required Parts | |||
| Part | Part Number | Description | Qty |
| 5 | 221-3416 | Pressure Sensor | 1 |
| 11 | 175-3700 | Connector Repair Kit | 1 |
| 11A (1) | 1U-5804 | Crimp Tool | 1 |
| 11B (1) | 8T-8729 | Connector Pin | 3 |
| 11C (1) | 102-8803 | Receptacle Kit | 1 |
| ( 1 ) | Part of 175-3700 Connector Repair Kit |
Machine Preparation for Service
- Ensure that the machine is on a smooth, horizontal surface. Ensure that the machine is away from working machines and personnel. Lower all implements to the ground. Install the wheel lean pin in the front axle. Install the articulation lock pin.
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Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury to persons on or near the machine. To prevent injury or death, make sure that the area around the machine is clear of personnel and obstructions before operating the machine. |
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Hydraulic oil pressure can remain in the hydraulic system on this machine after the engine and pump have been stopped. Serious injury can result if this pressure is not released before any service is done on the hydraulic systems. In order to prevent possible injury, release the hydraulic system pressure before working on any fitting, hose, or hydraulic component. Lower all attachments to the ground before service is started. If the hydraulic system must be serviced, tested, or adjusted with the attachment in the raised position, the attachments and lift cylinders must be supported properly. Always move the machine to a location away from the travel of other machines. Be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being made. |
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| NOTICE |
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Do not allow any dirt or foreign material to get into the hydraulic system during assembly, connection of lines, when components are filled with fluid, or during any maintenance operation. |
| 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. |
Note: The pressure in the hydraulic system must be released before hose assemblies or components can be removed or disconnected.
- Activate the parking brake. Place all implements on the ground and put the blade in the FLOAT position.
Note: Permit only one operator on the machine. Keep all other personnel away from the machine or in the view of the operator.
- If equipped, place the blade cushion in the ON position. Place the lift cylinders in the FLOAT position. The oil will return to the hydraulic tank. This will relieve pressure in the circuit.
- Stop the engine.
- Carefully loosen the filler cap on the hydraulic tank in order to release the pressure in the tank.
| NOTICE |
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Never remove the fill/vent plug from the hydraulic tank if the oil is hot. Air can enter the system and cause pump damage. |
- Make sure that all of the hydraulic pressure is relieved before any work is performed on the hydraulic system or any hydraulic component.
- Tighten the cap on the hydraulic tank.
Changing the Pressure Sensor
- Remove cover (1) .
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| Illustration 1 | g01086808 |
- Loosen hose (2) slowly in order to release any pressurized oil that may still be in the line.
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| Illustration 2 | g01086978 |
- Remove hose (2) .
- Remove plug assembly (3) .
- Install all wheel drive pressure sensor (5) into flushing and cooling valve (4) .
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| Illustration 3 | g01086980 |
- Disconnect the wiring harness from the former 124-4672 Pressure Sensor (6) .
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| Illustration 4 | g01087034 |
- Remove the bolts (7) .
- Remove the former 124-4672 Pressure Sensor (6) .
- Remove electrical connector (8) from wiring harness (9) .
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| Illustration 5 | g01087035 |
- Remove the three connector pins (10) from the wires.
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| Illustration 6 | g01087054 |
- Use Tool (11A) in order to install connector pins (11B) (not shown). Refer to Special Instruction, SEHS9615, "Servicing Deutsch HD and DT Style Connectors", "Terminal Crimp Procedure" for more information on installing connector pins.
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| Illustration 7 | g01087056 |
- Install the wires into electrical connector (11C) .
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| Illustration 8 | g01087085 |
(A) Socket (B) Socket (C) Socket | |
- Install the yellow wire into socket (A) .
- Install the black wire into socket (B) .
- Install the orange wire into socket (C) .
- Connect electrical connector (11C) to all wheel drive pressure sensor (5) .
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| Illustration 9 | g01087093 |
- Install cover (1) .
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| Illustration 10 | g01086808 |