G'day NormK and thanks again for all the help mate, see I probably would never have known and ran the mower without the shroud as I don't know much about these new model Victa 2 strokes. So thank you very much for pointing that out as I am new to these models.
I have been searching the internet for pictures on this model engine and parts lists to possibly grab some parts if they are still available.
Check out this video out I found on youtube, it's the same engine as the one I found and they were selling it on Gumtree a few years ago, I think it is missing this shroud also by the looks of it? What happens if you don't have the shroud? Probably would get a heap of rubbish getting into the fins at the bottom? But it would also make the engine run hotter as it helps to direct the air around the engine as you said?
Cheers!
Zip a dee doo dah, zip a dee ay, another trash picked Victa, hip hip Hooray!