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What You Need to Know About Water Outlets and Coolant Housings

The coolant housing or water outlet serves as the connection point between the engine and the upper radiator hose. The water outlet or coolant housing may be made of metal, plastic, or resin, depending on the vehicle’s manufacturer. As plastic or resin housings become increasingly popular for their advantages over traditional metal components, technicians need to know a few things about them.

How Can a Metal Water Outlet or Coolant Housing Fail?

Metal water outlets or coolant housings appear indestructible. In reality, metal is a precarious material. In addition to being susceptible to rust from exposure to high levels of water, metal can become warped over time, and also splinter-off metallic shavings into the cooling system. These factors pose major implications when replacing the thermostat. If the metal has warped, it may have damaged the installation point in the engine block, or metal shavings may have become lodged in other parts of the cooling system.

What Are the Advantages of Replacing the Complete Thermostat Housing Unit?

Unfortunately, the typical thermostat-only replacements of the past left auto technicians in limbo. Even after replacing the thermostat, small deficiencies or problems in the coolant housing could result in premature thermostat failure. As a result, the ideal solution would be replacing the entire thermostat housing unit. Yet, this implies a higher cost of replacement for metal outlets. Essentially, the added cost is the result of the energy used in creating a metallic water outlet.

What Are the Reasons a New, Plastic- or Resin-Type Housing or Outlet is Needed?

Metal can be subjected to temperature extremes, yet the constant heating and cooling of metal results in a deterioration of its quality. Furthermore, replacing all water coolant housings with metal housings can be costly and demanding, especially if the metals have become warped. Therefore, more manufacturers have turned to plastic or resin coolant housings.

A plastic or resin housing does not expand significantly when heated or cooled, which helps the functionality of the thermostat remain intact. Plastic or resin coolant housings can be removed from the engine block easier, and the cost of manufacturing plastic or resin housings is lower than manufacturing metallic housings. As a result, these savings can be passed on to the technician, and therefore, to the vehicle owner.

Plastic or resin water outlets or coolant housings offer many benefits over metal housings. As newer materials are used in place of metals, auto technicians need to understand why metallic water outlets fail, as well as the benefits of replacing the entire housing unit, in addition to how plastic or resin water outlets can deliver better functionality.