The thermostat helps to do a whole bunch of important things in your cooling system. Think of it as a halfback, it’s small, manages a whole bunch of components and can cause headaches if it stops doing its job. 

What is a thermostat? 

A thermostat is either a mechanical or electric valve that's found on the inlet set side of the engine's cooling system. At lower temperatures it stays closed and restricts the flow of coolant through the car. At higher temperatures it opens up and allows unrestricted flow to move all the available pressure through the system and cool the engine down.

Why do you need a thermostat? 

The thermostat stays closed when you cold start your car. This helps warm the motor up slowly and bring everything up to the right temperature. This helps extend the life of your motor. As the motor increases in temperature the thermostat opens more and more to manage the temperature and keep the right amount of coolant flowing. It does a neat job and it’s a critical part of your engine.

How to tell if you need a new thermostat

If your engine takes a long time to get up to temperature then it may indicate that the thermostat has failed. Other key indicators are that the engine overheats quickly or that you struggle to get hot air through your vents. These indicate that the thermostat is stuck closed. 

What’s involved in getting a thermostat replaced?

The mechanic will first locate the thermostat housing and disconnect any wiring or sensors attached to it. After draining the coolant, they will unbolt and remove the thermostat as well as its gasket and clean the mounting surface. They will then test the new thermostat and install it with a new gasket. They will then reconnect any wiring or sensors and refill the coolant. They will then run the engine up to temperature and test the system. 

How much does a thermostat replacement cost near Christchurch?

There’s a fair bit of labour involved for such a small part. Prices generally range from $225 to $550 

How often do I need a thermostat replaced?

They typically won’t fail unless there’s contaminants in the coolant or you use water instead of coolant. They will last over 150,000km in the right conditions. 

Is a broken thermostat unsafe?

It can overheat and seriously damage your engine, so it’s not something to play around with. If something goes wrong, get it replaced as soon as possible.

You can find a mechanic near Christchurch with My Auto Shop