Troubleshooting Oil Loss and Gain in the Bobcat 843: Causes and Solutions

[MikePhua]

The Bobcat 843 skid-steer loader is known for its power and versatility in a wide range of industries, from construction to landscaping. However, like all heavy machinery, it can sometimes experience mechanical issues that affect its performance. One common problem faced by operators is the loss or unexpected gain of oil, which can lead to serious complications if not addressed promptly. This article will explore the potential causes of oil loss or gain in the Bobcat 843, provide troubleshooting tips, and offer solutions to ensure your machine continues to operate efficiently.
Understanding the Bobcat 843's Hydraulic and Engine Oil System
The Bobcat 843, like most skid-steer loaders, uses hydraulic oil for powering attachments and performing lifting and pushing tasks. In addition, the machine also uses engine oil to lubricate and protect its internal components. Both systems are crucial for the smooth operation of the loader, and issues with oil can lead to a variety of performance problems.
Common Causes of Oil Loss in the Bobcat 843
Oil loss is a common issue that many Bobcat 843 owners face. If you notice that your machine is losing oil, it's important to address the issue immediately to prevent further damage. The potential causes of oil loss include:
1. Hydraulic System Leaks
The Bobcat 843’s hydraulic system is responsible for powering the machine’s various attachments, such as buckets, augers, and grapples. If there's a leak in the hydraulic lines, pumps, or hoses, hydraulic fluid may leak out, causing a loss of oil.
Potential Causes:

• Damaged Hoses or Fittings: Over time, the hydraulic hoses can wear out or become damaged from constant pressure, leading to leaks. Similarly, loose or worn fittings can result in oil seepage.
  
• Damaged Seals: Seals around the hydraulic cylinders or pumps can deteriorate, leading to oil leaks.
  
• Hydraulic Pump Failure: A failing hydraulic pump can cause excessive pressure in the system, leading to oil leakage.
  

Solution:

• Inspect hydraulic hoses, fittings, and pumps for signs of wear or damage. Replace any worn or damaged components immediately.
  
• Check the seals around the hydraulic cylinders and pumps. If you notice oil seepage, replace the seals to prevent further leaks.
  

2. Engine Oil Leaks
While the hydraulic system is a common source of oil loss, engine oil leaks can also be problematic for the Bobcat 843. These leaks often occur around seals, gaskets, or other parts of the engine.
Potential Causes:

• Worn or Damaged Seals/Gaskets: Over time, seals and gaskets can degrade, causing oil to leak from the engine. Common culprits include the valve cover gasket, oil pan gasket, or the seals around the oil filter.
  
• Cracked Engine Components: In rare cases, cracks in the engine block or cylinder head can lead to oil leaks. This may be caused by wear and tear or overheating.
  

Solution:

• Perform a thorough inspection of the engine, focusing on areas where seals and gaskets are located. Replace any worn gaskets or seals.
  
• If you suspect a crack in the engine, it’s important to have the machine inspected by a professional mechanic. Cracked engine components often require extensive repairs or replacement.
  

3. Excessive Oil Consumption
Sometimes, the Bobcat 843 may consume more oil than normal, leading to a noticeable drop in oil levels. While this may not involve an immediate oil leak, it can indicate that the engine or hydraulic system is using oil excessively.
Potential Causes:

• Worn Engine Components: Over time, engine parts like pistons, rings, and valves can wear out, causing the engine to burn oil. This is particularly common in older machines that have seen significant use.
  
• Overfilled Oil: If the engine oil was overfilled during a recent oil change, excess pressure can build up, causing oil to leak from seals or other parts of the engine.
  
• Improper Maintenance: Failing to change the oil regularly or using the wrong type of oil can contribute to excessive oil consumption. Dirty oil can cause internal components to wear out more quickly, leading to increased oil usage.
  

Solution:

• If excessive oil consumption is the issue, check the condition of the engine's internal components. If necessary, have the engine inspected and rebuilt to prevent further oil loss.
  
• Ensure that the engine oil is filled to the correct level. If the oil is overfilled, drain the excess oil and check for leaks that could have occurred due to pressure buildup.
  
• Stick to a regular maintenance schedule, including timely oil changes and the use of the correct oil type for your machine.
  

4. Contaminated Oil
Contaminated oil can cause significant problems in both the hydraulic and engine systems of the Bobcat 843. Contaminants like dirt, debris, and moisture can enter the oil system, leading to poor performance and potentially damaging internal components.
Potential Causes:

• Inadequate Filtration: If the oil filter is clogged or not functioning properly, contaminants can get into the oil system.
  
• Damaged Seals or Gaskets: Worn seals or gaskets in the engine or hydraulic systems can allow dirt and moisture to enter, contaminating the oil.
  
• Improper Oil Storage: If the oil is not stored or handled properly, it can become contaminated before it even enters the machine.
  

Solution:

• Regularly replace the oil filters and inspect them for damage or clogging. Ensure that the filters are correctly installed to prevent contaminants from entering the system.
  
• Inspect the engine and hydraulic system seals for damage and replace any worn seals or gaskets.
  
• Always store oil in clean, dry containers to prevent contamination before it is used in the machine.
  

Common Causes of Oil Gaining or Overfilling in the Bobcat 843
While oil loss is a more common issue, some operators may notice an unexpected gain in oil levels. This could be due to several factors, including the following:
1. Overfilled Oil Reservoir
If too much oil is added during maintenance, it can cause oil to appear to "gain" or overflow. This can happen if the oil is poured into the system without checking the level or if the machine is not on a flat surface during the oil check.
Solution:

• Always check the oil level while the machine is on a flat surface and follow the manufacturer’s recommended oil capacity. If the oil is overfilled, drain the excess to the appropriate level.
  

2. Fuel Contamination in Oil
In some cases, fuel can mix with the engine oil due to a malfunctioning fuel injector or a faulty fuel system. This results in an increase in the oil level, as the fuel mixes with the oil and causes it to become more diluted.
Solution:

• If you suspect fuel contamination in the oil, inspect the fuel system, including the injectors and fuel lines. Replace any faulty parts to prevent further contamination. In some cases, you may need to replace the engine oil and clean the system thoroughly.
  

3. Hydraulic Fluid Contamination in Engine Oil
If hydraulic fluid leaks into the engine oil, it can result in an increase in oil levels. This usually happens when seals between the hydraulic system and the engine fail, allowing hydraulic fluid to mix with the engine oil.
Solution:

• Inspect the hydraulic system for any leaks that may be allowing fluid to enter the engine oil system. Replace any damaged seals or gaskets and flush the engine oil system to remove contaminated fluid.
  

Conclusion
Oil loss or gain in the Bobcat 843 skid-steer loader can be caused by various factors, including leaks, worn engine components, or even contamination. To avoid further damage, it’s essential to address these issues as soon as they are identified. Regular maintenance, such as checking oil levels, replacing filters, and inspecting the hydraulic and engine systems, can help prevent oil-related problems. By staying proactive and following proper maintenance practices, you can ensure that your Bobcat 843 continues to perform efficiently and reliably on the job site.