HELP! Big coolant leak!!

[geraintthomas]

Brilliant, that's perfect. Thanks everyone for the information, hopefully it'll be cured with the newer cap and purging the air.

There's a Porsche dealer next to where I live (lucky me), and I gave them a ring. They said £9 for 1L of Porsche 50/50 coolant, and £18 for a brand new coolant lid with the part number ending in .04.

Perfect

[san rensho]

Originally Posted by Steve Tinker

Yes.

The cap is probably leaking - when the coolant cools the leaking cap allows air into the system. When you restart the car, the air expands and forced coolant out through the overflow - which is what you have.

1) Replace cap as suggested above.
2) Top up coolant with distilled water / Porsche coolant 50/50 mix.
3) Open the purge valve D shaped lever for at least 3 x heat cycles of the engine or for a few days. This allows air to be expelled.
4) Top up the coolant tank each morning as the level will drop as air is expelled.
5) If the air is getting to the system because your tank is cracked, you will see moisture under the carpet in the boot.

Good advice. I would only add that you find the steepest parking ramp you can find, stop the car on the ramp with the front of the car pointing down and the purge valve openand rev the car up a couple of times. Air tends to collect in the radiators and this is the easiest way to purge the air.

[geraintthomas]

So I topped it up with Porsche coolant and it's been absolutely fine since. I've just replaced the radiator cap with the revised one that ends in 04. Hopefully that was just a one off

Thanks guys.