Regarding diesels under the aft berths, there is no queston that they are less convenient, in benign conditions,
for checking fluid levels than diesels that are accessed through the transom steps/aft deck
. However, if you ever need to bleed, or repair a diesel
in order to assist in staying off a lee shore in extreme conditions (or in order to make harbour in advance of them becoming extreme), you would be thankful for diesels that are accessed from the interior
There is significantly less access to diesels mounted aft and this problem is exacerbated in heavy seas. Furthermore, by having to be outside and aft you are exposed to not only wind
and wave, but potentially to green water
. This is to say nothing of the electrical equipment
- ie. starter motors, solenoids, alternators, voltage regulators etc. that can be soaked in heavy rains/seas while the lids are open.
Think that you would never need to effect repairs/bleed the injectors in bad conditions? Think again. It is rough conditions that are most apt to create air locks, or to stir up impurities in the tanks
that will require bleeding; and, waterpump impellers etc. are just as apt (and according to Murphy's Law, more apt) to fail at the worst possible time.
Installing diesels under the aft berths dramatically increases access, convenince and safety
underway. It also keeps the weight out of one of the ends of the boat, important for two reasons: weight there increases the tendency to 'hobby-horse'; it also reduces reduces buoyancy aft, significant if you wish to run before a storm. As has already been pointed out, it can also lead to installing the saildrive
either aft of the rudders, or in front but too close to allow the installation
of folding props.
For the voyager, the installation
of the diesels in the Manta makes perfect sense. For those who intend to charter
a boat, or to sail near shore, in primarily good conditions, much less so.