08-24-2025, 03:07 PM
Machine Background
The Bobcat T190 Compact Track Loader is a popular, versatile machine used widely in construction, landscaping, and agriculture. Equipped with a reliable diesel engine and an efficient cooling system, the T190 is designed for demanding environments and continuous operation. Bobcat has continually enhanced cooling system designs in its compact loaders to ensure durability and thermal efficiency, addressing challenges posed by harsh work sites.
Symptom Description
A common coolant issue experienced on the T190 involves the coolant reservoir bottle remaining cold even after 45 minutes of operating. Additionally, when squeezing the upper radiator hose that connects to the water fill neck, water is observed pushing up into the reservoir. The lower radiator hose often has a spiral construction making it difficult to assess pressure or temperature by manual means.
Potential Causes and Diagnostics
Many operators note that air locks cause misleading temperature symptoms, requiring patient bleeding procedures, especially after coolant changes. Replacing spiral threaded or kinked hoses significantly improved flow and reduced overheating issues for some T190 owners. One mechanic shared that cold reservoir problems were traced back to a blocked radiator caused by dust accumulation in a forestry environment—regular cleaning prevented recurring faults.
Summary
Bobcat T190 coolant system issues such as a cold coolant reservoir and unusual hose pressure behaviors often stem from air locks, thermostat malfunctions, or clogged radiators and hoses. A methodical troubleshooting approach involving temperature checks, system bleeding, component inspection, and replacement helps restore reliable coolant circulation. Maintaining clean cooling components and timely service will minimize downtime and extend machine life.
The Bobcat T190 Compact Track Loader is a popular, versatile machine used widely in construction, landscaping, and agriculture. Equipped with a reliable diesel engine and an efficient cooling system, the T190 is designed for demanding environments and continuous operation. Bobcat has continually enhanced cooling system designs in its compact loaders to ensure durability and thermal efficiency, addressing challenges posed by harsh work sites.
Symptom Description
A common coolant issue experienced on the T190 involves the coolant reservoir bottle remaining cold even after 45 minutes of operating. Additionally, when squeezing the upper radiator hose that connects to the water fill neck, water is observed pushing up into the reservoir. The lower radiator hose often has a spiral construction making it difficult to assess pressure or temperature by manual means.
Potential Causes and Diagnostics
- Air Lock in Coolant System: One of the leading causes of coolant not circulating properly is air trapped inside the cooling system. Air locks prevent the normal flow of coolant through hoses and radiator, causing erratic temperature readings and cold spots within hoses and the reservoir.
- Thermostat Malfunction: A stuck thermostat can inhibit coolant circulation, preventing the engine from reaching optimal operating temperature. Replacing or testing the thermostat is a common diagnostic step which has shown mixed results in similar Bobcat models.
- Clogged Radiator or Hoses: Radiator blockages from dirt, debris, or corrosion reduce coolant flow. Spiral hoses may trap sediment or restrict flow internally. Cleaning or replacing affected hoses and radiators is often necessary.
- Water Pump Failure: The water pump is critical for circulating coolant through the engine and radiator. If the pump fails or the impeller is damaged, coolant movement stops, causing reservoir to remain cool and pressure inconsistencies at hoses.
- Manual Temperature Readings: Use a local thermometer or infrared heat gun near the thermostat housing and radiator hoses to verify temperature differences and coolant flow.
- Bleed the Cooling System: Purge trapped air by loosening bleed screws or running the engine with the radiator cap off at idle, refilling as necessary to reach full coolant level.
- Inspect and Replace Thermostat: Remove and test the thermostat by heating in water and observe the opening temperature. Replace if faulty or sticking.
- Check Radiator and Hose Integrity: Flush or replace clogged radiators and suspect hoses, paying special attention to spiral-lined hoses that may hide flow blockages.
- Water Pump Examination: Listen for unusual sounds or leaks, and verify pump performance by checking coolant circulation during warm engine operation.
- Air Lock: Air trapped in the coolant system, disrupting fluid flow.
- Thermostat: Valve controlling coolant flow to regulate engine temperature.
- Spiral Hose: Reinforced hose with internal spiral wire to prevent collapse under vacuum or pressure.
- Bleeding: The process of removing air pockets from coolant system to restore flow.
Many operators note that air locks cause misleading temperature symptoms, requiring patient bleeding procedures, especially after coolant changes. Replacing spiral threaded or kinked hoses significantly improved flow and reduced overheating issues for some T190 owners. One mechanic shared that cold reservoir problems were traced back to a blocked radiator caused by dust accumulation in a forestry environment—regular cleaning prevented recurring faults.
Summary
Bobcat T190 coolant system issues such as a cold coolant reservoir and unusual hose pressure behaviors often stem from air locks, thermostat malfunctions, or clogged radiators and hoses. A methodical troubleshooting approach involving temperature checks, system bleeding, component inspection, and replacement helps restore reliable coolant circulation. Maintaining clean cooling components and timely service will minimize downtime and extend machine life.
