Good engine!
It is a great engine, I pulled an Atomic 4 out of a 1970 Morgan 28 (Charlie Morgan, not an out island). We repowered with the 3 cylinder Vetus, I believe it was a 20hp, this was back in 1987. My father still owns the boat, it stays over in the Bahamas, I sailed it two months ago (June, 2002). The engine runs great - several years ago the heat exchanger did have to be replaced, but I believe that is the only major maintanance that has been needed in the last 15 years. It is very quiet and has been reliable. Having said that, I recommend carefully checking the size and your present engine bed to determine how extensive the modification will be. I just repowered my Hunter 31 last month, I first looked at a Vetus, but for my boat the modifications would have been very extensive so I went with a new Yanmar 2GM20F. Let me know if you have any other questions. Good luck.-Jon