Hello again.
It was water with oil floating on top. After skimming the oil off there wasn't much oil at all, about a dog bowl full.
As for the type of engine. I have only recently acquired the boat and the previous owner told me it was an sr2. To add to this the plate on the engine has the engine number 7295sr225m, which based off a bit of research is a number for an sr2. However the plate is on the air vent (you can see the plate in the first photo at the top of the thread). And of coarse the air vent is removable. And the engines are very similar.
Thanks for all your replys and that is as far as I have got so far.