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More to do if you replace a thermostat in your car

A properly functioning radiator cap plays a crucial role in maintaining the efficiency and safety of your vehicle’s cooling system. Here’s a detailed explanation to help your customer understand the importance of replacing both the thermostat and the radiator cap:

Significance of the Radiator Cap:

  • Pressure Maintenance: One of the primary functions of the radiator cap is to maintain pressure within the cooling system. If the cap fails or becomes worn out, it can lead to a drop in system pressure, reducing the coolant’s boiling point. This decrease in boiling point can trigger engine overheating.
  • Coolant Boiling Point: A declining boiling point due to a faulty radiator cap can cause the engine to overheat, potentially leading to significant engine damage.

Thermostat and Radiator Cap Replacement:

  • System Pressure: When replacing the thermostat, if the radiator cap is over three years old, it might not maintain the required pressure like a new cap. It’s essential to explain to your customer that replacing both the thermostat and the radiator cap ensures the vehicle operates within the specified temperature range and maintains proper system pressure.
  • Correct Pressure Range: Typically, the radiator cap is designed to maintain a pressure of around 15 psi. Using an incorrect or defective cap can result in either too low or too high system pressure, leading to various issues.

Potential Consequences of Improper Pressure and Boiling Fluid:

  • Fluid Boiling: A cooling system with the correct coolant ratio and proper pressure prevents fluid boiling. If the coolant boils, it can cause cavitation and cavitation erosion, resulting in severe damage to the water pump seal, impeller, pump casting, and other engine components.
  • Catastrophic Failure: Prolonged exposure to boiling fluid and improper pressures can lead to catastrophic failure of the cooling system and engine components, compromising vehicle safety and performance.

Role of the Reserve Tank:

  • Pressure Release: In extreme operating conditions or high ambient temperatures, the system pressure may exceed the design or desired levels. The radiator cap releases this excess pressure to maintain the recommended pressure range.
  • Coolant Capture and Replenishment: The reserve tank serves as a reservoir to capture the discharged coolant during pressure release from the radiator cap, preventing it from entering the environment. As the system cools down, a vacuum is created, drawing the discharged coolant back into the system from the reserve tank, ensuring the coolant level remains consistent.

In summary, educating your customer about the critical role of the radiator cap and the importance of replacing both the thermostat and the cap when necessary can help them understand the significance of regular maintenance and prevent potential cooling system issues, overheating, and engine damage.