help needed with a qualcast b66 cultmatic

Hi I have a b66 and it's been over heating with lots of smoke after it been running for about ten minutes, so I started stripping the engine down last night ( this is a first for me working on engines ) I have taken the pistons out and cleaned them ect and then I got a bit braver and decided to take the side panel off at the bottom of the engine , but when I opened it , in the bottom there was a plastic gear in three parts and some metal Pieces's , I'm not shore what they are but mite be the oil flicker thing . But I can't find no plans or drawings on the internet to find out for definite. i moved to Bulgaria from UK seven years ago and I've taken my b66 to four different mower repair shops today and they can't help as they have never seen one before so is here a online place for parts or do any of you have some parts n the back of your sheds. Thanks. Also what a great site this is , I showed it to my wife last night and she been looking at it most of the day .

Thank you , at least I know what the  parts are now. Just need to find some spairs for the old girl now and a  manual or photos so  I know how to refit Them. or if someone can tell me what motor it is . Thank for your help.will put another photo of the engine .

Photo 2

Thanks for the plans that's looks like mine so just need to find some parts now. Iand thanks one's again for all you help.

That isn't a B & S engine, it is a Qualcast engine, fitted to lots of Qualcast, Suffolk, Atco and Webb mowers in the 1980s. Spares should be no problem in the UK, a complete used mower can make under £30, but in Bulgaria I suspect they will be difficult to get.