I've undone the two hex bolts and let the coolant drain out

What should I do next before refilling?


I've heard I should put a hose in the expansion tank and let it flush itself out before refilling

I've also heard there are some drain plugs at the front of the car that need undoing too?


And, once it's done, what should I refill it with?

The coolant that came out of the car was green/yellow
Apparently the new stuff is pink?


Am I ok to flush the system with a hose then fill it with the pink stuff?

 

I would think you would want to drain the radiators as well. There are drain plugs on them. You also may want to disconnect the hoses under the car by the trans just to get everything out.

When you go to refill, do yourself a favor and get one of the vacuum coolant tools. It is a snap to refill with one. Not so much with out.

You will get a lot of opinions on coolant. I just used the Porsche stuff. Yes pink. It was like 23 bucks a gallon at sunset. Mix it 50/50. You could also through in some water wetter just for fun.

Good Luck!!

 

Apparently it is quite awkward to do

 

What's meant to be awkward about it?

I'm guessing there's more to it than just pouring new coolant into the expansion bottle then?

 

Yes, you need to bleed the air out of the system.Using a vacuum tool is best as stated by TurboTodd.

 

Apparently bleeding the air out the system is very difficult, mine has just had all the mods fitted and coolant swap etc and when it was being tuned on dyno it dumped all the coolant. Still air in the system!

 

If you drain from the hex plugs under the engine only about 8 liters drains out, this is less than a third of all the coolant,

If you want to drain most of the rest, as has been said, you need to drain the rads and disconnect the two main lines under the car next to the gearbox , it is also a good idea to disconnect the two heater hoses next to the gearbox as about 4 liters stays in the heater and heater lines.

At the front my car only had a drain plug on the center rad, the side rads didn't have drain plugs. I drained the center rad then disconnected the lower hoses on the main rads and a lot more came out, so the center drain plug doesn't do a very good job of draining the side rads.

After doing all this I got out 25 liters, out of the total capacity of 28 liters
If you want to make sure you've got all the old coolant out I would then reconnect everything and fill with water, run the car upto temp, then drain again before finally refilling with the new coolant.This is the only way to get all of the old coolant out if that what you want to do.


Its also a myth that the 996t is hard to bleed, its not, you just need to know a few things.

The first is that it won't bleed unless the wire clip is lifted up on the black valve on the header tank.

The second is that it won't bleed unless you rev the engine.

so to fill, first lift up the wire clip, fill the header tank to max then have an assistant rev the car to 3000 rpm, keep on filling the header tank keeping it on the max mark and you will find the coolant goes in nicely, keep filling while checking the temp gauge starts to rise.

The aim is to get the thermostat to open so water can circulate the whole system, eventually both of the main coolant lines near the gearbox should get hot telling you the thermostat has opened.Keep an eye on the temp gauge and stop if it goes over 90'c (195f), it shouldn't do

Shortly after this the level will stop dropping in the header tank.
Now is the time to put the header cap back on and go for a drive taking some spare coolant with you.

The temp should be normal at this point, you literally have to shake the last of the air out of the system so accelerate hard , brake and go around some bends, return home and let the car cool, once cool you will find the level will drop in the header tank so top it up to max. You may find it takes a couple of days until the level finally remains constant and the system is back to being totally full. Return the clip back to its flat position

I have used this method three times now without problem. Its also basically the same method Porsche uses.

And

 

Agree 100% with And996tt. On more thing I did and help me a lot was to raised the back of the car while filling....

 

How often should we change the coolant and is it worth doing it all the way or just an engine change?

 

From what I've read & heard the coolant has an unlimited lifespan in our engines

I'm changing mine due to engine work, no other reason