"Capt. JG" wrote in
:

Do all Perkins 4-108s smoke like that? I almost bought a boat that did
that, but it smoked at all rpms, so I passed.



No, they don't. It only smokes if the prop is too steep and you're shoving
more fuel into it than it has air to burn....turning it into carbon.

It'll smoke if you're going forward and pull hard astern...

That boat probably needed to have its injection timing done and its
injection set. Smoke doesn't hurt them, just wastes fuel.