Surely you remember prior discussions?

Run the blower and take a sniff, they'll be fine. The A4 runs smoother and quieter than nay diesel. They are a workhorse and you can get parts at Moyer and most NAPA stores. And as Tim mentioned, you can even get a new block from Moyer.

I'll concede on the fuel use, but it's a sailboat, you're sailing most of the time anyway.

Only thing really wrong about the A4 is people's irrational fear of them. I've heard of far more frequently about accidents involving propane stoves than A4 engines, yet oddly, there seems to be no great fear of propane.