RE: worst engine ever
My "worst" engine was an Austrlian Taipan 15 diesel. As an 11 year old, I just could not start it. So I sold it and bought an OS 15 II and never looked back.
Actually the Taipan was a really nice engine and if I still had it it would be quite valuable. I still have the remains of the OS. Starting it for the first time led to bloody fingers but we got there in the end. I think we were tougher (or more stupid) in those days.
I also had (and still have) a really nasty Super Tigre G20 15D diesel. It was made from cast off parts and worn out parts. (We were kids and we did not have much cash then so any motor that we could get was going to be used). It would run and run and run but it was totally clapped out. We called it "Joe Superloose" and if you got it tuned right you could win races with it. But get it slightly overcompressed or lean and it would slow down but not stop and you would have to limp along until the fuel ran out. Very embarrassing. Despite this, it would start easily hot or cold but with a Bartel's fibreglass prop it was deadly on the fingers and by this time I had learned to always use some form of finger protection.