GUIDE: Basic coolant change (W208)

[JSeaman]

Change your coolant when the car is cold, coolant is superheated when the car is hot as it is a pressurised system so never work on a hot car

Step 1 - See steps 1-5 of the oil change guide to remove the undertray

Step 2 - With the undertray removed, get some suitable vessels for catching fluids (the old coolant) ready

Step 3 - Lying with your head under the front of the car, on the passenger side you will find a small red bleed screw. You need to slacken this with a flatblade screwdriver

 

[JSeaman]

Step 4 - When you slacken the bleed screw, coolant will come out of the highlighted pipe, this takes a while though so it's quicker to remove a bigger hose (see step 7)

Step 5 - Catch all the coolant and dispose of at your local refuse dump

Step 6 - Remove the coolant filler cap

 

[JSeaman]

Step 7 - Now pop to the other side of the rad and undo the bottom hose

Step 8 - Once completely drained, you can refit the bottom hose

 

[JSeaman]

Step 9 - If you remove the drain plug totally there is an O ring you can replace then tighten this back up

Step 10 - Use a funnel to help you top up the antifreeze, use blue antifreeze

Step 11 - Refit the filler cap and run the car up to temperature checking for leaks (go for a drive to warm the car up quickly after you have done an initial visual inspection). Top up as required (but not when the coolant is hot!)

 

[duncanh]

Don't you also have to drain the coolant out of the cylinder block?

 

[Silver_Star]

Yes there is a drain plug on the block.

I also like to give it a flush in both directions with the hose pipe as well before adding the new coolant.

However the guide is entitled "Basic Coolant Change" so it is fine.

 

[JSeaman]

You hit the nail on the head there, I put it as a basic change because there were 3 things I consider in a normal (or 'advanced') change:

1. Drain the block
2. Change stat
3. Back flush the system

James

 

[wireman]

I would take off the filler cap as step one to let the coolant out faster.

 

[Miffy]

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