How To Change Your Car's Thermostat

How To Change Your Car's Thermostat

A thermostat is an important system in a car, so once it is tested faulty, it needs a replacement unit. This film provides the steps on removing your car's thermostat, how to determine if it's faulty, replacing a new unit and checking if it works.

The first thing is to make sure the vehicle is at cold temperature. It's not something you want to be doing while the vehicle is hot for obvious reasons. The thermostat is contained within this unit here.

The water is drained out of the vehicle, which will contain the antifreeze, into a suitable container so it does not spill all over the floor. Wear protective gloves and goggles as well. Remove the expansion bottle lid which is painted yellow.

The yellow items mean they're the stuff to be checked. Hence, the power steering fluid, the oil with the yellow symbol on it and so does the break fluid reservoir and the dip stick is also yellow. Most modern cars are fitted with a drain on the radiator like so.

The easiest way to do them is either with a two pence piece or a wash up which fits perfectly. By undoing the drain, the water will flow out. Catch it within a water-tight vessel and be careful because it will spray everywhere.

Now, re-secure the drain. Replace the thermostat. Remove the three vaults holding this thermostat housing in place.

Remove the thermostat casing and remember which way in the thermostat goes because it obviously goes with the flow of the water. There goes the old unit. Now, test it to see if it's faulty or not.

Test the thermostat in a cup of hot boiling water. Submerge the thermostat in the water for a few minutes and it should open up. If you see it open, if you see a gap there now, that shows the thermostat is working.

Once it starts to cool down, that will close. This is the thermostat in closed position. As you can see, there's no gap around here at all.

So, in this position, if the thermostat is not open, it is a faulty thermostat. For the replacement unit, check the unit as there may be some slight differences from different manufacturers. You may have a new water seal with that, a kit or a rubber ring.

In this particular model, it takes a rubber ring which fits over the edge of the thermostat housing like so. Once in place, that's the seal that the thermostat needs. Remember to put the thermostat back in the way it was removed, using the rubber seal around the edge.

The rubber seal itself causes the seal. Check the thermostat body to make sure that's clean and there's no foreign body in there like so. Reinsert the three vaults and retighten.

That's the new thermostat now in place. So now, what you need to do is refill the water system of the vehicle with antifreeze mixture which is 5% antifreeze to 5% water for this vehicle. If unsure, consult your main dealer.

Always ensure that the heat had been crossed and set to a hot division which opens all the vaults to allow the air to come out the heating system and avoid any air lumps. The heater must be turned off and the power turned off. But fill the system with the engine running.

Run the vehicle until the engine is hot. This is to check the thermostat's opening. You feel the temperature at the top right at the hose connected to the thermostat, keep the engine running until the fan cuts in and goes off again, then check your level.

You need to check the level once the vehicle is cooled down so you might just use the next day but then it might have minor air blockages. That's basically how to change a thermostat.