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The Cat 246 and Its Hydraulic Pilot Control System
The 2001 Caterpillar 246 skid steer loader was part of Cat’s early 2000s compact equipment lineup, designed for grading, material handling, and light excavation. With a rated operating capacity of 2,000 lbs and powered by a four-cylinder diesel engine, the 246 featured a pilot-operated hydraulic control system. Unlike electric-over-hydraulic setups found in later B, C, and D series machines, the original 246 used low-pressure pilot hydraulics to actuate the main control valves.
This system relies on smooth modulation of joystick inputs, regulated by pilot pressure and valve response. When functioning properly, it allows for precise loader and travel control. However, when pilot pressure is too high or valve response is erratic, the machine can become overly sensitive—leading to jerky starts, abrupt stops, and rocking during directional changes.
Symptoms of Jerky Operation and Abrupt Stops
Operators have reported that the 246 stops abruptly when releasing the joystick, causing the machine to rock violently. This rocking can be dangerous when operating near obstacles or loading tall trucks, especially with the bucket raised. Additional symptoms include:
Possible Causes and Diagnostic Path
To address jerky control behavior, consider the following inspection steps:
Solutions and Adjustments
To improve control behavior:
Operator Technique and Safety Considerations
Even with mechanical fixes, operator technique plays a role. Encourage smooth joystick transitions and avoid sudden directional changes. When working near trucks or structures, keep the bucket low during travel and avoid abrupt stops.
In one incident, a new operator reversed away from a truck with the bucket raised and experienced violent rocking—highlighting the need for training and awareness when handling sensitive controls.
Conclusion
Jerky controls on the 2001 Cat 246 are often caused by excessive pilot pressure, worn joystick components, or hydraulic flow restrictions. By inspecting the pilot circuit, adjusting pressure, and maintaining clean fluid, operators can restore smooth control and reduce rocking during operation. The 246 remains a capable machine, but its pilot system demands careful tuning and thoughtful handling to perform safely and effectively.
The 2001 Caterpillar 246 skid steer loader was part of Cat’s early 2000s compact equipment lineup, designed for grading, material handling, and light excavation. With a rated operating capacity of 2,000 lbs and powered by a four-cylinder diesel engine, the 246 featured a pilot-operated hydraulic control system. Unlike electric-over-hydraulic setups found in later B, C, and D series machines, the original 246 used low-pressure pilot hydraulics to actuate the main control valves.
This system relies on smooth modulation of joystick inputs, regulated by pilot pressure and valve response. When functioning properly, it allows for precise loader and travel control. However, when pilot pressure is too high or valve response is erratic, the machine can become overly sensitive—leading to jerky starts, abrupt stops, and rocking during directional changes.
Symptoms of Jerky Operation and Abrupt Stops
Operators have reported that the 246 stops abruptly when releasing the joystick, causing the machine to rock violently. This rocking can be dangerous when operating near obstacles or loading tall trucks, especially with the bucket raised. Additional symptoms include:
- Hopping during turns, especially on hard surfaces
- Overreaction to small joystick movements
- Difficulty maintaining smooth travel or feathered loader control
Possible Causes and Diagnostic Path
To address jerky control behavior, consider the following inspection steps:
- Hydraulic fluid level and condition: Ensure the reservoir is full and fluid is clean. Contaminated fluid can affect valve response.
- Hydraulic filters: Clogged filters can restrict flow and cause erratic pressure spikes. Replace both return and pilot filters if due.
- Pilot pressure regulator valve: This valve sets the pressure for the joystick control circuit. If it’s stuck or misadjusted, pilot pressure may exceed spec.
- Joystick linkage and spool wear: Mechanical wear in the joystick assembly can cause abrupt spool movement, leading to sudden hydraulic response.
- Lift and tilt cylinder leaks: While minor leaks may not affect control directly, they can contribute to uneven pressure distribution.
Solutions and Adjustments
To improve control behavior:
- Check pilot pressure using a gauge at the joystick circuit. Typical pilot pressure should be around 300–500 psi. If it exceeds this, adjust the regulator or replace the valve.
- Inspect joystick movement for smoothness. Lubricate linkages and check for binding.
- Replace hydraulic filters and flush the system if fluid appears milky or dark.
- Test machine on different surfaces to isolate traction-related hopping from hydraulic issues.
Operator Technique and Safety Considerations
Even with mechanical fixes, operator technique plays a role. Encourage smooth joystick transitions and avoid sudden directional changes. When working near trucks or structures, keep the bucket low during travel and avoid abrupt stops.
In one incident, a new operator reversed away from a truck with the bucket raised and experienced violent rocking—highlighting the need for training and awareness when handling sensitive controls.
Conclusion
Jerky controls on the 2001 Cat 246 are often caused by excessive pilot pressure, worn joystick components, or hydraulic flow restrictions. By inspecting the pilot circuit, adjusting pressure, and maintaining clean fluid, operators can restore smooth control and reduce rocking during operation. The 246 remains a capable machine, but its pilot system demands careful tuning and thoughtful handling to perform safely and effectively.
