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Why You Need to Complete a Full Cooling System Repair, Not Just the Thermostat and Gasket

An overheating engine seems to automatically point to a problem with the thermostat. Thermostat failure is one of the most common reasons for overheating engines. However, replacing the thermostat and gasket is not a comprehensive cooling system repair, and automotive technicians need to understand a few things about performing a complete cooling system repair.

What Can Cause Thermostat Failure?

The thermostat may fail for a variety of reasons, which include the following:

  • Cooling fans may be damaged.
  • Plugged passages can lead to the overheating of the thermostat.
  • The radiator may be damaged.
  • Impellers in the water pump may have broken or eroded.
  • The serpentine belt may have broken.

It’s important to remember that each of these potential problems in the cooling system can cause failures within other parts of the cooling system.

Why is it Important to Diagnose the Complete Cooling System?

The aforementioned causes of thermostat failure indicate problems in other parts of the cooling system. If an automotive technician fails to diagnose the complete cooling system, the chances of premature thermostat or gasket failure increase.

For example, a damaged radiator may result in leaking coolant and lead to an increase in engine temperatures. As the thermostat attempts to correct this problem, the thermostat may become stuck in the open position. The leaking antifreeze and open thermostat result in the overheating of the vehicle, and thermostat failure. As a result, the vehicle owner must have the new thermostat replaced once more. Ultimately, replacing the thermostat and gasket is comparable to placing a Band-Aid on a bigger problem when not diagnosing the complete cooling the system.

When a Thermostat Fails, What Else Could Be Damaged?

Thermostat failure will lead to the overheating of an engine, which can damage critical components in the engine. Many of these components are actually part of the cooling system. For example, an overheating engine may cause the water pump impellers to degrade significantly. Therefore, the vehicle owner will need to have the thermostat and gasket replaced, as well as replace the water pump. As explained by Repair Pal, The typical cost of water pump replacement ranges from $296 to $400. Additionally, part of the water jacket may melt and require replacement, the radiator may overheat and develop a leak, and oil can actually begin to smolder and burn within the cylinders. As a result, the repercussions for not diagnosing the cooling system in its entirety can incur significant costs.

Replacing the thermostat and gasket is part of routine maintenance as a vehicle ages. However, auto techs should stay vigilant and understand how a thermostat may actually indicate other problems within the cooling system. By performing a thorough check of the cooling system, auto techs can reduce costs for both the shop and the vehicle owner, which helps promote a positive technician-customer relationship, as well