How do you drain ALL the coolent from a MK2 caddy?

[Caddymobile]

year 2000 caddy van 1.9 Sdi Diesel
I opened both the bottom big hose to the bottom of the rad & the top big hose to the top of the rad, about 3 litres of coolant drained out. I think there is another 3 litres inside somewhere as book says 6.3 litres capacity. What am I doing wrong?
Thanks in advance for help:confused:

[kenney]

Hi There will still be coolant in the engine block,you need to remove the thermost otherwise it will take ages to drain.