The water outlet connects the engine to the upper radiator hose. When the cooling system thermostat is located at the outlet it is sometimes called the thermostat housing. Most water outlets are aluminum but can also be made of cast iron, steel or nylon.

Many outlets come with plugs for when a vehicle requires a temperature switch for one model but no switch for a second model.

Which Thermostat Is Right For You?

What Temperature Thermostat Do I Need?

Thermostats have a “rated” temperature (such as 180F or 195F). This is the temperature the thermostat will start to open, releasing heated coolant from the engine into the radiator. The thermostat will fully open once the coolant gets another ten or fifteen degrees warmer.

Cooling System Maintenance | Tips & Tools

Without regular maintenance, cooling system components will degrade and fail prematurely, which can lead to costly engine damage. Protect your engine with simple preventative maintenance:

• Completely drain and flush the system using Cooling System Flush prior to installation. Flushing the system is critical to prevent system contamination and failure.
• Consider replacing the Radiator Hoses (and Hose Clamps) and Radiator Cap as part of routine preventative maintenance. System contamination can cause these parts to degrade and fail over time, which can lead to severe engine damage from overheating.
• Refill radiator with fresh Coolant / Antifreeze according to the volume and formula specified in your Owner's Manual. Inspect levels and condition every year.