Atomic 4 Engine Rebuild or upgrade?

[Crazer]

I will be the voice of dissent and say you should keep the A4. I would recommend replacing it with a Moyer Marine factory rebuilt unit if you're unsure about the engine you have in the boat. The A4 is very reliable, and most importantly when it does break down it is easy and cheap to fix. The diesel will be reliable but much fussier and more expensive to fix when it does break down (and it will) whereas with the A4 I guarantee you any issue you run into you can take care of yourself. That is partly just because of the simplicity of the engine and in part due to the depth of support available to A4 owners through Moyer Marine and the associated online forums.

On the other hand, I do not disagree it is too much motor (although it does not produce the reputed 30 hp) and to each his own. It sounds like you have the resources to pay someone else to take care of the motor, so maybe that is not an issue for you. Diesels are certainly very popular these days. I would NOT under ANY circumstances put an outboard on it if you can afford not to. I hate the things, they are extremely fussy (ethanol makes this much worse) and will give you more trouble than anyone wants to deal with. Especially avoid four strokes. They will last you a couple years at best before they start to have issues, and once they start having problems, they do not stop.