"Larry" wrote in message
That's true in a Hatteras with twin turbo 8V92TA's in it....but not in a
sailboat with a two-cylinder Yanmar idling slow. Even wide open, it's
still two little diesel pistons pumping slowly up and down, not much of a
threat to pumping out the stinky head hose smell on other threads at
all...
(c;

Many diesel powered sailboats do have exhaust blowers, whether they need
them or not. I have owned 4 inboard sailboats and three had blowers - not
sure about the other, but it was a saildrive in it's own box.

But, I have to admit I hardly ever turned the blower on. Usually the engine
only ran for 15 or 20 min, to exit harbour, so no need. But on long windless
trips, I sometime remembered to turn it on, if it was getting steamy down
below.

It may be a good idea to wire the blower into the starter switch circuit so
it is always running when the engine runs or add a thermal switch set at 35C
or so. This would perhaps help the refrig unit too, because it exhausts into
the cockpit lockers which are open to the engine compartment.

GBM