Caterpillar CB24B Low Oil Pressure Issues and Engine Protection Strategies

[MikePhua]

The CB24B and Caterpillar’s Compact Compaction Lineage
The Caterpillar CB24B is a compact tandem vibratory roller designed for asphalt finishing, patching, and small-scale compaction projects. With an operating weight of approximately 3,000 kg and drum widths of 1,200 mm, the CB24B is widely used in urban infrastructure, parking lots, and bike paths. Powered by a CAT C1.5 diesel engine, the machine delivers smooth performance with dual vibratory drums and intuitive controls.
Caterpillar, founded in 1925, has long dominated the compaction equipment market. The CB24B was introduced as part of the B-series, offering improved visibility, simplified service access, and enhanced operator comfort. Thousands of units have been sold globally, and the model remains a staple in rental fleets and municipal road crews.
Terminology Notes

• Oil Pressure: The force exerted by engine oil as it circulates through bearings, lifters, and journals, typically measured in psi or bar.
  
• Oil Pressure Sensor: An electronic or mechanical device that monitors oil pressure and sends signals to the control panel or ECU.
  
• Relief Valve: A spring-loaded valve that regulates maximum oil pressure to prevent damage to engine components.
  

Symptoms of Low Oil Pressure and Field Observations
Operators may encounter:

• Warning lights or alarms on the control panel
  
• Engine derating or shutdown during operation
  
• Audible ticking or knocking from the valve train
  
• Delayed startup lubrication, especially in cold weather
  
• Excessive wear on camshaft or crankshaft bearings
  

A paving crew in Florida reported that their CB24B began flashing a low oil pressure warning after 20 minutes of runtime. Despite normal oil levels, the engine would derate intermittently, affecting compaction speed and consistency.
Root Causes and Diagnostic Strategy
Low oil pressure can result from a range of mechanical and electrical issues. Common causes include:

• Worn Oil Pump
  • Reduced flow rate and pressure under load
    
  • Diagnosed via mechanical pressure gauge at test port
    
• Faulty Oil Pressure Sensor
  • Sends incorrect readings to ECU or dashboard
    
  • Confirmed by comparing sensor output to manual gauge
    
• Clogged Oil Filter or Pickup Screen
  • Restricts flow and causes pressure drop
    
  • Requires inspection and replacement
    
• Internal Engine Wear
  • Excessive clearance in bearings or journals
    
  • Detected via oil analysis and teardown inspection
    
• Relief Valve Stuck Open
  

• Prevents pressure buildup
  
• Requires disassembly and spring tension check
  

Diagnostic steps:

• Connect mechanical oil pressure gauge and compare readings at idle and full throttle
  
• Inspect oil filter for debris or collapse
  
• Check sensor wiring and connector integrity
  
• Perform oil analysis for metal particles or viscosity breakdown
  
• Remove oil pan and inspect pickup tube and pump assembly
  

Repair Procedure and Component Recommendations
To restore oil pressure:

• Replace oil pressure sensor with OEM-rated unit
  
• Install new oil filter and verify bypass valve function
  
• Inspect and replace oil pump if flow is below spec
  
• Clean pickup screen and verify tube alignment
  
• Check relief valve spring and seating surface
  
• Refill with manufacturer-recommended oil grade and viscosity
  

Recommended components:

• CAT C1.5 oil pressure sensor kit
  
• High-efficiency oil filter with anti-drainback valve
  
• Oil pump assembly rated for 40–60 psi output
  
• Relief valve spring and seat kit
  
• SAE 10W-30 or 15W-40 oil with API CI-4 or higher rating
  

A technician in Ontario rebuilt a CB24B’s oil pump after discovering scoring on the rotor and housing. Post-repair, the machine maintained consistent pressure across temperature ranges and completed a full paving season without further alarms.
Preventive Maintenance and Long-Term Solutions
To prevent future oil pressure issues:

• Change engine oil every 250 hours or per seasonal schedule
  
• Replace oil filter at each oil change
  
• Inspect sensor and wiring during quarterly service
  
• Monitor oil pressure readings and log anomalies
  
• Use oil analysis to detect early wear or contamination
  

Some fleet managers install dual oil pressure sensors—one for ECU and one for manual gauge—to cross-check readings. Others retrofit bypass alarms to alert operators before pressure drops reach critical thresholds.
Recommendations for Operators and Technicians

• Maintain a service log with oil changes, pressure readings, and sensor replacements
  
• Train operators to respond promptly to oil pressure warnings
  
• Stock spare sensors, filters, and oil for field repairs
  
• Partner with CAT dealers for updated service bulletins and retrofit kits
  
• Consider oil pump inspection during major engine service intervals
  

For machines operating in hot climates or extended duty cycles, synthetic oil and upgraded filtration are recommended.
Conclusion
Low oil pressure in the Caterpillar CB24B is more than a nuisance—it’s a warning sign that demands attention. Whether caused by sensor faults or internal wear, prompt diagnosis and repair are essential to protect the engine and maintain compaction performance. In the rhythm of asphalt finishing, pressure is not just a number—it’s the pulse of reliability.