Upgrading the Cooling Fan System on the John Deere 320E Skid Steer

[MikePhua]

The 320E and Deere’s Mid-Frame Loader Evolution
The John Deere 320E is part of the E-series skid steer lineup introduced in the early 2010s, designed to meet Tier IV emissions standards while improving operator comfort and hydraulic performance. With a rated operating capacity of 994 kg (2,190 lbs) and a net engine power of 66 hp, the 320E became a popular choice for contractors, landscapers, and municipal fleets. Its compact frame, vertical lift geometry, and compatibility with high-flow attachments made it versatile across job types.
John Deere’s E-series marked a shift toward electronically controlled engines, improved diagnostics, and more refined cooling systems. However, the factory-installed variable-speed hydraulic fan on the 320E has drawn mixed reviews, especially in hot climates or dusty environments where cooling demands spike unpredictably.
Terminology Annotation

• Hydraulic Fan: A cooling fan driven by hydraulic pressure, often variable-speed and controlled by engine temperature.
  
• Belt-Driven Fan: A mechanically driven fan powered by a belt connected to the crankshaft, offering consistent airflow.
  
• Thermostatic Control: A system that adjusts fan speed based on coolant temperature, optimizing fuel efficiency.
  
• Reverse Flow Fan: A fan capable of reversing direction to blow out debris from the radiator and oil cooler.
  

Why Convert the Fan System
Operators in high-debris environments—such as demolition, forestry, or feedlot work—often report overheating issues with the stock hydraulic fan. The variable-speed logic, while efficient under normal conditions, may not respond quickly enough to sudden heat spikes or clogged radiators. Additionally, hydraulic fans are more complex and expensive to repair, with failures often linked to solenoids, sensors, or control modules.
Benefits of converting to a belt-driven fan include:

• Constant airflow regardless of hydraulic logic
  
• Simpler mechanical layout with fewer failure points
  
• Easier troubleshooting and lower replacement cost
  
• Improved cooling in high-load or high-ambient conditions
  

In one grading crew in Arizona, a 320E was retrofitted with a belt-driven fan after repeated overheating during summer trenching. The conversion reduced coolant temperatures by 10–15°F under load and eliminated fan-related fault codes.
Conversion Strategy and Component Selection
Converting from hydraulic to belt-driven cooling requires careful planning. Key components include:

• Crankshaft pulley with fan drive capability
  
• Belt tensioner and idler pulleys
  
• Fan hub and clutch assembly (if using thermostatic clutch)
  
• Radiator shroud modification or replacement
  
• Mounting brackets and alignment jigs
  

Suggested specs:

• Fan diameter: ~18–20 inches
  
• Blade pitch: Optimized for airflow at 2,000–2,500 rpm
  
• Belt type: Serpentine or V-belt depending on pulley design
  
• Clearance: Minimum 1 inch between fan tips and shroud
  

In a fabrication shop in Alberta, a custom bracket was machined to mount a belt-driven fan on a 320E. The team used a fan clutch from a Deere 5065E tractor and adapted the shroud to maintain airflow direction. The result was a quieter, more reliable cooling system with improved service access.
Electrical and Control Considerations
If the original hydraulic fan is tied into the ECU, removing it may trigger fault codes or limp mode. Solutions include:

• Reprogramming the ECU to ignore fan feedback
  
• Installing a dummy load or resistor to simulate fan signal
  
• Using a thermostatic clutch to mimic variable-speed behavior
  
• Adding a manual override switch for fan engagement
  

In one municipal fleet in Georgia, technicians installed a toggle switch to manually activate the fan clutch during high-load operations. Operators appreciated the control and reported fewer overheating incidents during asphalt work.
Maintenance and Long-Term Reliability
Belt-driven fans require periodic inspection but are generally more robust than hydraulic systems. Maintenance tips include:

• Check belt tension monthly and adjust as needed
  
• Inspect pulley alignment and bearing wear every 500 hours
  
• Clean radiator fins weekly in dusty environments
  
• Replace fan clutch every 2,000 hours or if slippage occurs
  
• Use high-temp grease on fan hub bearings during service intervals
  

Recommended upgrades:

• Install a reverse-flow electric pusher fan for radiator cleaning
  
• Add a coolant temperature gauge with audible alarm
  
• Use silicone hoses for better heat resistance
  
• Apply anti-corrosion coating to fan blades and brackets
  

In a forestry operation in Oregon, a 320E with a belt-driven fan and reverse-flow pusher fan ran over 3,000 hours without cooling faults, even during summer mulching.
Final Thoughts
Converting the John Deere 320E from hydraulic to belt-driven fan cooling is a practical solution for operators facing heat-related downtime. While the factory system is efficient under controlled conditions, real-world demands often call for simpler, more aggressive airflow. With careful planning, quality components, and attention to electrical integration, the conversion can extend engine life, reduce service costs, and improve machine uptime.
In the steady spin of blades and the rush of cool air, reliability isn’t just engineered—it’s earned, one retrofit at a time.