Bobcat S650 Fuel Pickup: Troubleshooting, Maintenance, and Solutions

[MikePhua]

The Bobcat S650 is a powerful and versatile skid-steer loader that is well-suited for a wide range of applications, including construction, landscaping, and material handling. Like any heavy equipment, maintaining its fuel system is crucial to ensuring optimal performance and avoiding breakdowns. One key component of the fuel system is the fuel pickup, which plays an important role in delivering fuel from the tank to the engine. Problems with the fuel pickup system can lead to performance issues, ranging from rough idling to engine stalling. In this guide, we will delve into the common issues related to the Bobcat S650 fuel pickup, how to troubleshoot them, and the steps you can take to maintain the system.
Understanding the Fuel Pickup System in the Bobcat S650
The fuel pickup system in the Bobcat S650 is designed to transport fuel from the fuel tank to the engine’s fuel injectors. It consists of several key components, including:

• Fuel Tank: The main reservoir that holds the diesel fuel for the machine.
  
• Fuel Pickup Tube: A tube that extends into the fuel tank to draw fuel into the system. It is connected to the fuel filter and the rest of the fuel system.
  
• Fuel Filter: This component removes contaminants and debris from the fuel before it reaches the engine, ensuring the engine runs smoothly.
  
• Fuel Pump: The pump sends fuel under pressure through the system, delivering it to the engine for combustion.
  
• Fuel Lines: These hoses carry the fuel from the pickup tube and pump to the fuel injectors.
  

The fuel pickup system’s primary function is to ensure that clean fuel flows smoothly from the tank to the engine without any interruptions, ensuring efficient engine performance.
Common Problems with the Fuel Pickup in Bobcat S650
Over time, several issues may arise with the fuel pickup system that can affect the performance of the Bobcat S650. Understanding these common problems can help operators identify and resolve them quickly to avoid costly repairs.

1. Fuel Pickup Clogging
   • Symptoms: The engine may start to sputter, stall, or have trouble starting, especially when the fuel tank is low. In some cases, the machine may run for a while and then suddenly stop.
     
   • Cause: Dirt, debris, or water in the fuel can clog the fuel pickup tube or filter, obstructing fuel flow and causing engine performance issues.
     
   • Solution: Clean the fuel pickup tube and filter. If debris or water is found, drain the fuel tank and replace the fuel filter. It’s also a good idea to inspect the fuel lines for any blockages.
     
2. Air in the Fuel System
   • Symptoms: The engine may run erratically, with poor throttle response, rough idling, or stalling, particularly when starting.
     
   • Cause: Air entering the fuel system, especially around the fuel pickup or fuel lines, can cause an airlock, preventing fuel from reaching the engine.
     
   • Solution: Bleed the air from the fuel system. This can be done by loosening the fuel line fittings near the fuel filter and allowing the air to escape before tightening them again. Ensure that all fuel line connections are properly sealed to prevent air from entering the system.
     
3. Faulty Fuel Pickup Tube or Strainer
   • Symptoms: The machine may experience fuel starvation, with the engine stalling or running unevenly, especially at low fuel levels.
     
   • Cause: A damaged or cracked fuel pickup tube can cause the fuel to draw air, or a worn-out fuel strainer can prevent proper fuel flow.
     
   • Solution: Inspect the fuel pickup tube and strainer for any cracks, blockages, or signs of damage. Replace the tube or strainer if necessary to restore proper fuel flow.
     
4. Fuel Pump Malfunction
   • Symptoms: The engine may fail to start, or the fuel delivery to the engine may be inconsistent, leading to stalling or sluggish performance.
     
   • Cause: A malfunctioning fuel pump can result in inadequate fuel pressure, disrupting the entire fuel system.
     
   • Solution: Check the fuel pump for any signs of wear or damage. Measure fuel pressure to ensure it is within the manufacturer’s specified range. If the fuel pump is not functioning correctly, it will need to be repaired or replaced.
     
5. Water Contamination in the Fuel
   • Symptoms: The engine may run rough, or you may notice water in the fuel filter or fuel bowl.
     
   • Cause: Water can accumulate in the fuel tank, especially if the machine is stored outdoors or exposed to rain. This can cause fuel to separate and lead to poor engine performance or damage to internal components.
     
   • Solution: Drain the fuel tank completely and replace the fuel filter. Add a fuel water separator or fuel additive designed to remove water from the system. Regularly inspect the fuel filter for signs of water contamination.
     

How to Troubleshoot the Fuel Pickup Issues on the Bobcat S650
If you are facing performance issues with the fuel pickup system on the Bobcat S650, here is a step-by-step troubleshooting guide:

1. Step 1: Inspect the Fuel Tank
   • Check the fuel tank for any signs of water contamination or debris. If the fuel looks dirty or cloudy, consider draining the tank and refilling it with fresh, clean diesel fuel.
     
2. Step 2: Examine the Fuel Pickup Tube
   • Remove the fuel pickup tube from the tank and inspect it for any blockages, cracks, or wear. Ensure that the strainer at the end of the tube is clean and free of debris. If the tube is damaged, replace it with a new one.
     
3. Step 3: Check the Fuel Filter
   • Inspect the fuel filter for signs of clogging or contamination. If the filter is dirty, replace it with a new one to ensure clean fuel reaches the engine.
     
4. Step 4: Test the Fuel Lines
   • Check the fuel lines for any signs of leaks, cracks, or blockages. Tighten any loose fittings and replace any damaged hoses to prevent air from entering the system.
     
5. Step 5: Bleed the Fuel System
   • If air is suspected to be trapped in the fuel system, follow the proper procedure to bleed the fuel lines. This can usually be done by loosening the fuel line fittings and allowing air to escape until the fuel flows consistently.
     
6. Step 6: Inspect the Fuel Pump
   • Check the fuel pump to ensure it is providing the correct fuel pressure. If the fuel pressure is too low, the pump may be faulty and require replacement.
     

Maintaining the Fuel Pickup System on the Bobcat S650
Maintaining the fuel pickup system is essential for avoiding common problems and ensuring the Bobcat S650 runs smoothly. Here are some key maintenance tips:

1. Regular Fuel Filter Replacement
   • Change the fuel filter at regular intervals as specified in the Bobcat S650 owner’s manual. This will help prevent contaminants from entering the engine and damaging the fuel system.
     
2. Use Clean, Quality Fuel
   • Always use clean, high-quality diesel fuel to avoid water contamination or the buildup of dirt and debris in the system. Keep the fuel tank sealed to prevent moisture from entering.
     
3. Inspect the Fuel System Regularly
   • Periodically inspect the entire fuel system, including the fuel pickup tube, lines, filters, and pump, for any signs of wear, damage, or contamination. Catching small issues early can prevent larger problems from developing.
     
4. Store the Machine Properly
   • When not in use, store the Bobcat S650 in a dry, sheltered area to prevent water from entering the fuel system. If the machine is going to be stored for an extended period, consider draining the fuel tank to avoid the accumulation of water or fuel degradation.
     

Conclusion
The Bobcat S650 is a highly reliable skid-steer loader, but like any machine, its fuel system requires proper care and maintenance to ensure optimal performance. Problems with the fuel pickup system, including clogs, air in the system, and fuel contamination, can lead to engine stalling, poor performance, and costly repairs. By regularly inspecting and maintaining the fuel pickup system, including the fuel filter, fuel pickup tube, and fuel pump, operators can prevent these issues and keep their machine running smoothly. Proper fuel system care not only extends the lifespan of the Bobcat S650 but also ensures it remains a productive and dependable asset on any job site.