How to Install a Radiator Thermostat How to Install a Radiator Thermostat

What You'll Need
180 degree thermostat
Gasket for thermostat
Ratchet Wrench
Crescent wrench
Socket wrenches
Drain pan

The radiator thermostat controls the rate at which coolant is sent through to maintain the overall engine temperature. This device is located at the end of the coolant pipe near the rear of the radiator. Changing the radiator thermostat isn’t a complex job, though you will need specialist tools in order to do it.

Step 1 - Accessing the Thermostat

You can’t install a new radiator thermostat until you’ve taken out the old one. To start, you’ll need to drain the coolant from the radiator until it’s below the level of the thermostat. Open the valve at the bottom of the radiator and drain into a pan—don’t just let it run into the ground. You can dispose of your old coolant in a sealed container and there are many places you can take it for disposal.

You only need to drain the radiator enough so that you won’t lose fluid when you remove the thermostat. You can judge the level by tracing the coolant supply hose from the top of the radiator back to the engine. This is where the radiator thermostat is located.

Now. you will need to loosen the clamp where the hose meets the neck of the thermostat. Make sure you have a long screwdriver as this can be hard to reach. When the hose is loose enough, pull it free of the radiator thermostat neck. Loosen the hose from the radiator and put aside to give yourself more room to work.

Step 2 - Remove Old Thermostat

Use a ratchet wrench and socket to remove the neck fasteners on the thermostat. You’ll need an extension on the wrench in order to reach them more easily. Loosen each of the fasteners in turn and then remove them. When you’ve done this, you’ll be able to take out the radiator thermostat neck which will allow you to see the radiator thermostat. It’s very easy to pull out but make sure you also take out the old gasket with it.

After this, you’ll need to clean the housing surface so it will be ready for the new gasket and fitting. A clean surface ensures no grit or grime can get into small spaces around the radiator thermostat at a later stage.

Step 3 - New Thermostat

Put the new 180-degree radiator thermostat in place, ensuring that the front tab points toward the front of the engine. Secure the gasket firmly over the opening before putting the radiator neck back into place. You’ll need to tighten each of the bolts in turn gradually, making sure you have all of them partially tightened before going round and finishing the job.

Return the hose to its proper place, tightening the clamps on both ends. Once this is done,  you’ll need to make sure the radiator valve is closed. Fill the radiator with a mix of ½ coolant, ½ distilled water. Run the engine and check the coolant level again, adding more of the mix if necessary.

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