1960 Yardman

Hello, I recently purchased an old Lawnmower. I'm trying to find an engine schematic, but I'm having trouble figuring out what engine it has. I believe it is a 1960 Yard-Man Mode 3050. It lists as 5.5hp.. The tag on the engine lists it as 143.31600 with serial number 9129110. If I cross referenced that accurately I've seen it listed as a Tecumseh v55 engine. I still can't seem to find any schematic for parts. Can anyone please shed some light on this?