I have had to fill the header tank up twice today but I can't see where the water is going as there is no steam coming from the engine bay and also the oil is clean (no milky residue).

Any body got any ideas?

 

A cooling system pressure tester will show it up if it is external.

 

Had this on my old 98 - turned out that the radiators often get hair-line cracks in the end tanks - VERY tricky to trace - I'd take 'nice guys' advice and get it checked for holding pressure.

Also, start it up when cold, run for 20 seconds then stop. Take off the pressure cap - if there's pressure there, it'll be the head gasket leaking into the water system.....

2 key things to remember (from PAINFUL experience)

1) Don't just ignore it and keep topping up
2) Don't forget that its winter - if you're filling up with water, then you're diluting the anti-freeze mixture and the system may freeze overnight....

Good Luck !

Mark

 

I also had same problem and it was the radiator end tank on the drivers side split facing the front of the car , the split was a couple of inches long and hard to trace at first as its just a small hairline crack when cold and as it gets hotter the crack opens up , very common problem !

 

It is the end cap on the rad, where is best place and also cheapest to get a rad from?

 

I got mine from API for a decent price - can't remember what it was though

 

Any onther places?