How to flush coolant?

  1. #1
    Searched a few threads but its all pretty vague as i don't know where to start.
    Basically over the last couple of days iv noticed my coolant has had a bit of brown in it, like brown foam. i took the coolant temp sensor out and it was also covered in brown sludge, its hardly any and i checked coolant today, its still blue but with brown swirls in it, doesnt smell of petrol but smells like burnt oil tbh. the coolant hasnt gone down. Nor is there any gunk on filler cap. and heaters are fine. so thinking about puting in new coolant. how would i do it as i cant find any guides on where to begin. Cheers anyway
  2. #2
    http://www.saxperience.com/forum/showthread.php?t=98877

    also, mine is exactly the same as yours, slightly brown, but otherwise absolutely fine