3.8 litres according to the Lindsay Porter w/s manual (less if you haven't changed the filter. However, in practice you will not be able drain every drop of oil out. I find that I get out about 3l, and put 3l back in.
If you can measure how much you've taken out then that will give you a good idea. Either you need to look at the dip stick, and I'd expect it to be well past the max mark
.
I find that it can be hard to get accurate readings from the dip stick when the oil's just been filled. It needs to stand for a while, and then have a look, otherwise you'll find that the oil's all up the dipstick anyway.
Good Luck! :dead: