CAT 246 Drive Motor Shaft Removal

[MikePhua]

The CAT 246 skid steer loader is known for its impressive power, compact design, and versatility on the job site. As with any heavy equipment, maintaining its drivetrain components is crucial for optimal performance. One such critical component is the drive motor, which plays a key role in powering the wheels or tracks of the machine. In this guide, we will walk through the process of removing the drive motor shaft on a CAT 246, including the necessary tools, steps, and troubleshooting tips.
Understanding the CAT 246 and Its Drive Motor
The CAT 246 is part of Caterpillar's line of compact track loaders and skid steers, designed for use in confined spaces where larger machines cannot operate. The CAT 246 features a high-performance drivetrain powered by a hydraulic system that drives its wheels or tracks. The drive motor shaft, integral to this system, transfers power from the motor to the wheels, enabling the machine to move.
Over time, issues such as wear, damage, or malfunctioning of the drive motor shaft may occur. When this happens, the shaft must be removed and either repaired or replaced to restore the machine's functionality.
Common Issues That Require Drive Motor Shaft Removal

1. Oil Leaks:
   A common sign that the drive motor shaft may need attention is the appearance of oil leaks around the motor or shaft. These leaks can stem from damaged seals, worn gaskets, or cracks in the shaft itself.
   
2. Loss of Power or Torque:
   If the machine loses power or torque, particularly when attempting to move or lift, the drive motor shaft may be slipping or misaligned. This can be caused by wear or damage to the shaft.
   
3. Abnormal Noises:
   Grinding, whining, or any unusual noises coming from the drive motor could indicate that the shaft is damaged or the bearings are failing.
   
4. Erratic Movement:
   If the machine’s movement becomes jerky or inconsistent, it may be due to a faulty drive motor shaft or damaged components in the motor assembly.
   

Tools and Equipment Needed for Shaft Removal
Before starting the shaft removal process, ensure you have the following tools:

• Torque Wrench: For safely removing bolts without damaging the threads.
  
• Socket Set: A variety of sockets, including deep sockets, to fit various bolts and fasteners.
  
• Hydraulic Jack and Stands: For safely lifting the machine and providing adequate clearance for removal.
  
• Impact Wrench: To remove stubborn bolts or fasteners.
  
• Sealant Remover: To remove any old gaskets or sealant from the motor assembly.
  
• Pry Bar: For gently loosening the shaft if it's stuck or jammed.
  
• New Shaft Seals and Gaskets: To replace any worn or damaged seals during reassembly.
  
• Safety Equipment: Gloves, goggles, and protective footwear for safety during the procedure.
  

Step-by-Step Guide to Drive Motor Shaft Removal

1. Prepare the Machine
   Start by ensuring the machine is turned off and has cooled down if it was in operation. Place the machine on a flat, stable surface and engage the parking brake. Lift the machine using a hydraulic jack, and secure it with jack stands to ensure it remains stable during the removal process.
   
2. Remove the Wheels or Tracks
   Depending on whether you are working on a wheeled or tracked version of the CAT 246, begin by removing the wheels or tracks. This will give you better access to the drive motor and its components.
   
3. Disconnect the Hydraulic Lines
   The drive motor is powered by hydraulic fluid, so before disassembling any components, you need to relieve the hydraulic pressure. Disconnect the hydraulic lines connected to the motor, using a bucket or pan to catch any fluid that may leak out.
   
4. Remove the Motor Housing or Guard
   Using your socket set or impact wrench, remove any bolts securing the motor housing or protective guard around the drive motor. This will expose the motor assembly and give you access to the shaft.
   
5. Loosen the Motor Mounting Bolts
   Locate the motor mounting bolts securing the drive motor to the frame of the machine. These bolts may be quite tight, so use a torque wrench or impact wrench to loosen and remove them. Ensure you keep track of the bolts and washers as they will be needed for reassembly.
   
6. Remove the Motor Assembly
   Once the motor is disconnected from the frame, carefully remove the motor assembly. This may require using a pry bar to gently lift the motor off its mounting. Be careful not to damage any other components during this process.
   
7. Access the Drive Motor Shaft
   With the motor assembly removed, you should now have direct access to the drive motor shaft. Depending on the model, the shaft may be secured with retaining rings, bolts, or other fasteners. Use the appropriate tools to loosen and remove these fasteners.
   
8. Remove the Drive Motor Shaft
   Once the fasteners are removed, gently pull or slide the drive motor shaft out of its housing. If the shaft is stuck, apply a small amount of lubricant or sealant remover to loosen it. Be sure to support the shaft to avoid damaging it during removal.
   
9. Inspect the Shaft and Components
   After removal, inspect the shaft for signs of wear, damage, or bending. Check the surrounding bearings, seals, and housing for any issues that may have caused the shaft failure. If the shaft is excessively worn or damaged, it will need to be replaced. Also, inspect the motor housing for any signs of cracks or other damage.
   
10. Install the New Shaft
    If you are replacing the drive motor shaft, now is the time to install the new one. Carefully slide the new shaft into place and secure it using the appropriate fasteners. Ensure the shaft is properly aligned with the motor assembly and that all components are securely fastened.
    
11. Reassemble the Motor and Hydraulic System
    Once the shaft is in place, reassemble the motor by reversing the steps you followed during removal. Reconnect the hydraulic lines, reattach the motor housing or guard, and secure the motor back onto its mounting points.
    
12. Test the Machine
    After reassembly, lower the machine back to the ground and check the hydraulic system for leaks. Test the machine by running it at low speeds initially to ensure everything is functioning properly and that the drive motor shaft is securely in place.
    

Common Challenges and Solutions

1. Stuck Shaft
   If the shaft is difficult to remove due to corrosion or wear, use a penetrating lubricant to loosen it. In some cases, tapping the shaft gently with a mallet can help free it from its housing.
   
2. Damaged Seals
   During reassembly, ensure that the new seals and gaskets are installed properly to avoid leaks. Failing to replace damaged seals can result in hydraulic fluid leaks and further damage to the motor.
   
3. Misalignment
   Proper alignment is critical when reinstalling the shaft and motor assembly. Take extra care to ensure everything lines up correctly, as improper alignment can cause additional wear or even failure of the new shaft.
   

Conclusion
Removing and replacing the drive motor shaft on a CAT 246 skid steer is a detailed process that requires careful attention to detail and the right tools. By following the proper steps and taking the time to inspect all related components, operators can restore the machine's drivetrain to optimal performance. Regular maintenance and early detection of issues such as leaks, power loss, or unusual noises can help prevent major repairs and extend the lifespan of the drive motor and other critical components in the CAT 246.