Troubleshooting the CAT 955K: Common Issues and Solutions

[MikePhua]

The Caterpillar 955K is a versatile track loader that has been a staple in heavy equipment for decades. Known for its durability and power, the 955K is used in a variety of industries, including construction, mining, and forestry. However, like all heavy machinery, the CAT 955K is not immune to issues that can hinder its performance. This article explores some of the common problems faced by owners and operators of the CAT 955K, provides insights into troubleshooting these issues, and suggests solutions to keep the machine running smoothly.
Understanding the CAT 955K
The Caterpillar 955K, introduced in the 1960s, is one of the earlier models of track loaders designed for heavy-duty tasks. It was built for efficiency in earthmoving, material handling, and lifting operations. The machine features a diesel engine, hydraulic system, and durable tracks for traction and stability on rough terrains.
Despite being an older model, the 955K is still widely used, particularly in the used machinery market. Its solid build and ability to operate in tough conditions make it a reliable workhorse, though it requires proper maintenance to keep it in optimal condition.
Common Issues with the CAT 955K
While the CAT 955K is known for its reliability, it does face several issues over time, primarily related to its age and the wear and tear that comes with regular use. Below are some common problems encountered with this machine.
1. Hydraulic System Issues
Hydraulic systems are central to the performance of a track loader like the CAT 955K. If there is a hydraulic failure or reduced performance, it can severely limit the loader’s efficiency.

• Symptoms: Slow movement of the bucket, lack of lifting power, or erratic movements.
  
• Possible Causes: Low hydraulic fluid levels, air in the hydraulic system, leaking hoses or seals, or a malfunctioning hydraulic pump.
  
• Solutions:
  • Check Fluid Levels: Ensure that the hydraulic fluid is at the recommended level. Low fluid can cause inadequate pressure, leading to weak performance.
    
  • Inspect for Leaks: Inspect the hoses, cylinders, and seals for leaks, which are common in older equipment. Replace any damaged parts promptly.
    
  • Bleed the System: Air trapped in the hydraulic lines can cause erratic behavior. Bleed the system to remove air and restore smooth operation.
    
  • Pump Maintenance: If the hydraulic pump is malfunctioning, it may need to be repaired or replaced. This is a more complex issue that may require professional service.
    

2. Engine Starting Problems
As with many older machines, starting issues are a common complaint among CAT 955K owners. This can be due to a variety of engine-related issues.

• Symptoms: The engine cranks but does not start, or it takes multiple attempts to get the engine running.
  
• Possible Causes: Weak battery, fuel delivery problems, clogged fuel filters, or ignition system faults.
  
• Solutions:
  • Battery Check: A weak or dead battery is a common cause of starting problems. Check the battery voltage and replace it if necessary.
    
  • Fuel System Inspection: Ensure the fuel lines and fuel filters are clean and free of blockages. Clogged filters can restrict fuel flow to the engine, preventing it from starting.
    
  • Glow Plug Testing: If your model uses glow plugs for cold starts, make sure they are functioning correctly. Faulty glow plugs can cause starting issues in colder weather.
    
  • Inspect the Starter Motor: A worn starter motor may struggle to turn the engine over. If this is the case, the starter motor may need to be serviced or replaced.
    

3. Track Issues
The CAT 955K, being a track loader, relies heavily on its tracks for stability and movement. Over time, tracks can become worn or damaged, which can affect the machine’s performance.

• Symptoms: Uneven track wear, slippage, or the tracks coming off the sprockets.
  
• Possible Causes: Worn-out track links, damaged sprockets, or improperly adjusted track tension.
  
• Solutions:
  • Track Adjustment: Regularly check the tension on the tracks. Over-tightened or loose tracks can cause uneven wear and slippage. Adjust the track tension according to the manufacturer’s guidelines.
    
  • Track Wear Inspection: Inspect the track links for signs of excessive wear or damage. If the links are worn down, they may need to be replaced.
    
  • Sprocket Inspection: Check the sprockets for damage. Worn sprockets can cause the tracks to come off or wear unevenly. Replace the sprockets if necessary.
    

4. Overheating
Overheating is another common problem that can lead to engine or hydraulic system damage. The CAT 955K’s cooling system, including the radiator and fan, plays a crucial role in maintaining optimal operating temperatures.

• Symptoms: High engine temperature readings, steam or coolant leaks.
  
• Possible Causes: Low coolant levels, clogged radiator, malfunctioning cooling fan, or a damaged water pump.
  
• Solutions:
  • Coolant Check: Ensure that the coolant levels are adequate. Low coolant can cause the engine to overheat.
    
  • Radiator Cleaning: A clogged radiator can prevent proper airflow, leading to overheating. Clean the radiator fins and ensure they are free of debris.
    
  • Fan and Water Pump Inspection: Inspect the cooling fan and water pump for proper operation. If the fan is not turning or the pump is not circulating coolant properly, they may need to be replaced.
    

5. Electrical System Failures
Electrical issues are common in older machines due to wiring degradation and component wear. These issues can range from problems with the alternator to faulty electrical connections.

• Symptoms: Loss of power to lights, gauges, or other electrical components; battery not charging.
  
• Possible Causes: Faulty alternator, broken wiring, or damaged fuses.
  
• Solutions:
  • Alternator Test: Check the alternator’s output to ensure it is charging the battery correctly. A faulty alternator can lead to electrical problems and starting issues.
    
  • Wiring Inspection: Inspect all wiring for signs of wear, corrosion, or damage. Replacing damaged wires can restore proper function to the electrical system.
    
  • Fuse Replacement: If electrical components stop working, check the fuses and replace any that are blown.
    

General Maintenance Tips for the CAT 955K
To prevent issues and keep your CAT 955K running efficiently, regular maintenance is essential. Here are some general maintenance tips:

• Lubrication: Regularly lubricate moving parts, including the loader arms, tracks, and hydraulic cylinders, to prevent excessive wear and ensure smooth operation.
  
• Fluid Changes: Change the engine oil, hydraulic fluid, and coolant at regular intervals as recommended by the manufacturer to avoid contamination and overheating.
  
• Component Inspection: Regularly inspect the tracks, sprockets, hydraulic hoses, and other critical components for wear and tear, replacing any damaged parts promptly.
  
• Air Filter Cleaning: Clean or replace the air filter regularly to ensure the engine gets sufficient airflow and to prevent dirt from entering the engine.
  

Conclusion
The CAT 955K is a robust and reliable machine, but like all heavy equipment, it requires regular maintenance and occasional troubleshooting to keep it operating at peak performance. Understanding common issues such as hydraulic failures, engine starting problems, track wear, overheating, and electrical system faults is essential for diagnosing and fixing problems quickly. Regular inspections, proper lubrication, and fluid changes can go a long way in extending the life of the machine and preventing major breakdowns. By following these guidelines and addressing issues promptly, you can keep your CAT 955K working efficiently for years to come.