Diagnosing No-Start Conditions on the Caterpillar 246 Skid Steer

[MikePhua]

The CAT 246 and Its Mechanical Profile
The Caterpillar 246 skid steer loader was introduced in the early 2000s as part of CAT’s B-series compact equipment lineup. Designed for versatility in construction, landscaping, and municipal work, the 246 featured a robust frame, pilot-operated joystick controls, and a reliable diesel engine—typically a Perkins 3044C or CAT-branded variant producing around 74 horsepower. With an operating weight of approximately 7,500 lbs and a rated operating capacity of 2,000 lbs, the 246 became a popular choice for mid-size contractors and rental fleets.
Caterpillar, founded in 1925, has sold hundreds of thousands of skid steers globally. The 246 was known for its mechanical simplicity, ease of service, and compatibility with a wide range of attachments. However, like any machine, it can experience no-start conditions that require methodical troubleshooting.
Common No-Start Scenarios and Initial Checks
When a CAT 246 won’t start, the issue typically falls into one of three categories:

• Electrical system failure
  
• Fuel delivery problem
  
• Safety interlock or sensor malfunction
  

Initial inspection steps:

• Check battery voltage and terminal condition
  
• Inspect fuses and relays in the main panel
  
• Verify that the seat switch and lap bar sensors are functioning
  
• Confirm that the fuel tank has clean diesel and the fuel shutoff is open
  
• Listen for fuel pump priming and starter solenoid click
  

Terminology notes:

• Solenoid: An electromechanical switch that engages the starter motor when energized.
  
• Interlock system: A safety feature that prevents engine start unless certain conditions are met (e.g., operator presence, parking brake engaged).
  

In Ontario, a contractor found his CAT 246 completely unresponsive. After testing voltage, he discovered a corroded ground strap between the frame and engine block. Replacing the strap restored full electrical function.
Electrical System Diagnostics
Electrical faults are a leading cause of no-start conditions. The CAT 246 uses a 12V system with a starter relay, ignition switch, and multiple safety circuits.
Diagnostic steps:

• Measure battery voltage (should be 12.6V or higher)
  
• Load test the battery to confirm capacity
  
• Check starter relay for continuity and voltage drop
  
• Inspect ignition switch contacts for wear or carbon buildup
  
• Test starter solenoid for engagement signal
  
• Verify ground connections and cable integrity
  

Suggested tools:

• Multimeter with continuity and voltage settings
  
• Load tester for battery health
  
• Jumper leads for bypass testing
  
• Wiring diagram for reference
  
• Dielectric grease for terminal protection
  

In Tennessee, a grading crew traced a no-start issue to a failed ignition switch. The contacts had worn internally, preventing voltage from reaching the starter relay. Replacing the switch resolved the problem.
Fuel System Troubleshooting
If the engine cranks but doesn’t fire, fuel delivery is the next suspect. The CAT 246 uses a mechanical injection pump with an electric fuel shutoff solenoid.
Fuel system checks:

• Inspect fuel filter for clogging or water contamination
  
• Prime fuel system using manual pump if equipped
  
• Test fuel shutoff solenoid for voltage and actuation
  
• Check injector lines for leaks or air intrusion
  
• Bleed air from system after filter replacement
  

Suggested upgrades:

• Install a clear inline fuel filter for visual inspection
  
• Add a water separator with drain valve
  
• Use winter-grade diesel in cold climates
  
• Replace rubber fuel lines with braided hose for durability
  

In South Africa, a vineyard crew found their CAT 246 wouldn’t start after sitting for a week. The fuel had gelled due to low temperatures. After flushing the system and switching to winter diesel, the machine started reliably.
Safety Interlocks and Sensor Behavior
The CAT 246 includes multiple interlocks to prevent accidental start or movement. These include:

• Seat switch
  
• Lap bar sensor
  
• Parking brake switch
  
• Neutral gear sensor
  

Troubleshooting tips:

• Sit in the seat and lower lap bar to test interlock logic
  
• Wiggle connectors and check for loose pins
  
• Use jumper wires to bypass suspected faulty switches
  
• Scan for fault codes if equipped with diagnostic port
  
• Replace worn switches with OEM-rated parts
  

In New Zealand, a contractor bypassed a faulty seat switch temporarily to move his machine off a jobsite. He later replaced the switch and added a rubber boot to protect it from moisture.
Preventive Maintenance and Long-Term Reliability
To avoid future no-start issues:

• Inspect battery terminals monthly and clean with baking soda solution
  
• Replace fuel filters every 250 hours
  
• Test starter and alternator annually
  
• Keep wiring harnesses protected from abrasion and rodents
  
• Log all electrical and fuel system repairs for future reference
  

Suggested spares to stock:

• Battery terminals and ground straps
  
• Starter relay and ignition switch
  
• Fuel filters and shutoff solenoids
  
• Safety switches and sensor connectors
  
• Wiring diagram and service manual
  

In Florida, a demolition crew added battery disconnect switches to their fleet. This prevented parasitic drain and extended battery life during seasonal downtime.
Operator Stories and Field Wisdom
In Alberta, a snow-clearing team found their CAT 246 wouldn’t start after a deep freeze. The battery had dropped below 11V, and the starter couldn’t engage. After installing a block heater and battery warmer, cold starts became routine.
In Poland, a forestry crew used a CAT 246 for trail maintenance. After repeated no-starts due to vibration-damaged wiring, they rerouted the harness through a flexible conduit and added strain relief clips.
Conclusion
When a CAT 246 won’t start, the solution lies in methodical diagnostics and attention to detail. Whether the culprit is electrical, fuel-related, or a safety interlock, each system offers clues that guide the repair. With proper tools, preventive care, and a technician’s intuition, even the most stubborn no-start becomes a solvable puzzle—and the machine returns to work with confidence.