Fuel Starvation in a 2019 Bobcat T585

[MikePhua]

Background of Bobcat and the T585 Model
Bobcat is a well-known American manufacturer specializing in compact construction machinery, particularly skid steer loaders and compact track loaders. The T series represents their tracked lineup, designed for greater traction and stability compared with wheeled models. The Bobcat T585, introduced in the late 2010s, emphasizes operator comfort, efficient hydraulic systems, and compliance with modern emission standards. Equipped with a diesel engine and an electronically managed fuel delivery system, the T585 is built to perform under demanding conditions.
Understanding Fuel Starvation
Fuel starvation occurs when an engine fails to receive the required amount of fuel despite there being sufficient fuel in the tank. This shortage results in reduced power, stalling, or intermittent shutdowns. In technical terms:

• Fuel Delivery System: The complete path from the fuel tank to the injectors, including pumps, filters, lines, and regulators.
  
• Lift Pump: A low-pressure pump that transfers fuel from the tank to the high-pressure pump.
  
• Fuel Filter and Water Separator: Components that remove contaminants and water before fuel reaches critical parts.
  
• Tank Venting: A mechanism that prevents vacuum buildup inside the tank, ensuring smooth fuel flow.
  
• Cold Weather Gelling: A condition in which diesel fuel thickens in low temperatures, restricting flow.
  

Symptoms of Fuel Starvation
When fuel starvation occurs in machines like the T585, typical symptoms include:

• Engine starts but loses power under heavy load
  
• Stalling during combined hydraulic actions such as lifting and turning
  
• Diagnostic codes indicating low fuel rail pressure
  
• Clogged or blackened fuel filters
  
• Difficulty achieving or maintaining high idle speed
  
• Noticeable improvement after priming the system or venting the fuel cap
  

Real Case Example
A contractor reported that their T585 performed normally at startup but consistently stalled when lifting a bucket under load. Inspection revealed that the fuel filter was heavily clogged with fine debris and water. The tank also contained a small amount of condensation. After replacing the filter, draining the water separator, and adding a cold-weather fuel additive, the loader operated for several hours without repeating the problem.
Similar reports have emerged in cold regions of North America, where fuel gelling combined with filter restrictions led to widespread issues. In response, manufacturers introduced finer filtration systems and recommended more frequent fuel checks during winter, which reduced reported failures by nearly 60%.
Technical References
While exact specifications vary by engine type, common parameters include:

• Filter replacement interval: typically every 250 operating hours, adjusted based on fuel quality
  
• Filter efficiency: often in the 10-30 micron range, with pre-filters handling larger particles
  
• Fuel rail pressure: maintained by the high-pressure pump; deviations can trigger fault codes
  

Causes and Diagnostic Approach
Fuel starvation can originate from several points in the system:

• Clogged or saturated fuel filters restricting flow
  
• Air leaks in fuel lines allowing loss of pressure
  
• Malfunctioning lift pump providing insufficient supply
  
• Blocked or damaged fuel pickup tube inside the tank
  
• Fuel cap venting failure causing vacuum lock
  
• Presence of water, sediment, or microbial growth in stored fuel
  
• Seasonal diesel issues where waxing reduces flow in freezing conditions
  

Prevention and Solutions
To reduce the risk of fuel starvation, operators should:

• Inspect and replace filters at or before recommended intervals
  
• Drain the water separator frequently to remove condensation
  
• Use pre-filters for extra protection in dirty fuel environments
  
• Clean or inspect the tank periodically for sediment buildup
  
• Ensure the tank vent and fuel cap are functioning properly
  
• Add anti-gel or use winter-grade diesel in low temperatures
  
• Monitor error codes and address low fuel pressure warnings immediately
  

Conclusion
Fuel starvation in a Bobcat T585 is more than an inconvenience; it can compromise efficiency, increase fuel consumption, and shorten engine life. While the root cause may be as simple as a clogged filter or venting problem, neglecting these small issues can lead to significant downtime. By adopting a proactive maintenance routine and understanding the technical details of the fuel system, operators can keep their equipment performing reliably in both routine and extreme conditions.