Coolant Leak Troubleshooting on the Caterpillar IT24 Loader

[MikePhua]

The IT24 Loader and Its Cooling System Design
The Caterpillar IT24 integrated tool carrier was introduced in the late 1980s as part of Cat’s push to offer multi-functional wheel loaders capable of handling forks, buckets, grapples, and snow blades with equal efficiency. With an operating weight of around 25,000 lbs and a net power rating of approximately 145 horsepower, the IT24 became a staple in municipal fleets, construction yards, and industrial sites. Its articulated frame, quick coupler system, and robust hydraulic setup made it ideal for material handling and site prep.
The cooling system on the IT24 is designed to regulate engine temperature under heavy load and variable ambient conditions. It includes a radiator, water pump, thermostat, coolant reservoir, and a network of hoses and gaskets. Like many older Caterpillar machines, the IT24 uses a pressurized closed-loop cooling system, which relies on consistent pressure and flow to prevent overheating.
Terminology Clarification

• Coolant leak: The escape of engine coolant from the sealed cooling system due to cracks, worn seals, or pressure failures.
  
• Water pump: A belt-driven or gear-driven pump that circulates coolant through the engine and radiator.
  
• Thermostat housing: The enclosure that holds the thermostat and connects coolant passages.
  
• Weep hole: A small hole in the water pump body designed to release coolant when internal seals fail.
  

Common Leak Points and Symptoms
Operators may notice coolant loss in the IT24 due to:

• Drips or puddles under the machine after shutdown
  
• Steam or vapor from the engine bay during operation
  
• Low coolant level in the reservoir despite regular top-offs
  
• White residue or staining around hose clamps and fittings
  
• Engine temperature spikes under load or during idle
  

A contractor in Alberta reported that his IT24 began losing coolant during winter snow removal. After inspecting the radiator and hoses, he discovered a slow leak from the water pump weep hole, indicating seal failure. Replacing the pump restored system integrity and prevented further overheating.
Inspection Strategy and Leak Detection
To locate the source of a coolant leak:

• Start with a cold engine and inspect all visible hoses, clamps, and fittings
  
• Use a pressure tester to pressurize the cooling system and observe for leaks
  
• Check the radiator core and seams for cracks or corrosion
  
• Inspect the thermostat housing and gasket for seepage
  
• Examine the water pump body and weep hole for signs of leakage
  
• Look for coolant trails around the head gasket and block mating surfaces
  

Recommended tools:

• Cooling system pressure tester with adapter for Cat reservoir cap
  
• UV dye and blacklight for tracing small leaks
  
• Torque wrench for clamp and housing bolts
  
• Infrared thermometer to monitor temperature gradients
  

A technician in Georgia used UV dye to trace a persistent leak on an IT24 and found a hairline crack in the upper radiator tank. The component was replaced with a remanufactured unit, and the machine returned to full duty.
Repair Procedures and Component Replacement
Once the leak is identified:

• Drain coolant into a clean container for reuse or disposal
  
• Remove affected components such as hoses, pump, or radiator
  
• Clean mating surfaces and inspect for corrosion or warping
  
• Install new gaskets and torque bolts to manufacturer specifications
  
• Refill with Cat-approved coolant and bleed air from the system
  
• Monitor temperature and pressure during test run
  

Safety tips:

• Allow engine to cool fully before opening the reservoir
  
• Wear gloves and eye protection when handling coolant
  
• Dispose of old coolant according to local environmental regulations
  
• Use only compatible coolant types to avoid chemical reactions
  

A fleet manager in Texas replaced all coolant hoses on his IT24 units during annual service and added silicone sleeves to high-wear areas. This reduced mid-season failures and improved uptime across the fleet.
Preventive Maintenance and Long-Term Reliability
To prevent future leaks:

• Replace coolant every 2,000 hours or as recommended
  
• Inspect hoses and clamps quarterly for wear or looseness
  
• Flush the radiator annually to remove scale and sediment
  
• Use distilled water when mixing coolant to prevent mineral buildup
  
• Monitor coolant pH and additive levels with test strips
  

Operator tips:

• Avoid overfilling the reservoir, which can cause pressure spikes
  
• Let the engine idle briefly before shutdown to stabilize temperature
  
• Keep radiator fins clean and free of debris
  
• Report any signs of coolant loss immediately for inspection
  

A crew in British Columbia implemented a cooling system checklist as part of their daily walkaround. This helped catch early leaks and reduced engine overheating incidents by 70% over one season.
Conclusion
Coolant leaks on the Caterpillar IT24 loader are often caused by aging components, pressure imbalances, or seal degradation. With structured inspection, proper tools, and disciplined maintenance, these issues can be resolved before they lead to engine damage or downtime. The IT24’s rugged design rewards proactive care, and its cooling system—though simple by modern standards—remains effective when kept clean, sealed, and properly serviced. For operators working in demanding conditions, coolant integrity is not just a technical detail—it’s a safeguard for productivity.