The boat has a 260 HP Yanmar turbo diesel engine. Max speed at full throttle is 18 mph. This has to be some kind of a record for sailboats. We cruise at 14 mpt at less than 1/2 throttle.
engine is big for a boat of this size, but we wanted the ability to punch thru
heavy seas at high speed. The
strut, shaft, bearings, mounts and all drive train components are oversized
and designed for extra long life. The
engine is mounted under the cockpit. The 20 inch diameter Max prop is full feathing for greatly reduced drag when sailing.
The engine's position has monumental advantages:
1. Safety. All engine thru
hulls, exhaust tubing, muffler, shaft log, strut and engine water hoses and
rudder are behind a solid, watertight bulkhead. If a thru hull or hose fails, or if the prop, shaft, strut or
rudder strikes an underwater object hard enough to cause damage, the rear compartment will fill to about 12" deep, but the bulkhead will protect the boat from flooding. This is a major safety advantage, since these are the items that are
the most vulnerable to damage that could cause loss of the boat.
2. Soundproofing. This is the quietest and most vibration free engine
installation you will find on any production sailboat. Noise levels in the main cabin are unbelievably low. Here are some decibel readings. For
the boats, readings were taken at 8 knots. A few cars were
thrown in for comparison. For the
cars, readings were taken on smooth freeways, windows closed, at 60 mph. A 10 point change in decibel readings means a doubling of the
Beneteau 35s5 78
Freedom 38 85
Cadillac Sedan de Ville 72
Ford Taurus 76
engine noise on long passages can wear you down. The injector clatter on most modern diesels can be murder. Most sailboat engines are in the main cabin, and are so loud that
conversation is difficult. A few hours of that and you will be ready to shut it off. Under power with the rear engine, it is like sailing. The
muffler and prop, often sources of objectionable
noise, are also isolated from the main cabin. This boat is quiet.
Rudder control. The rear
engine position places the propeller right near the rudder, so the prop
blast has lots of effect on steering ability, both in forward and reverse. If the helm is put over hard, the transom will swing in the direction
that you intend before the boat starts to move forward or to the rear. This is really useful in docking. Few sailboats have better steering control, at any speed, whether going
forward or backwards.
Engine heat and odor. Engines
get hot, and give off unpleasant fuel smells. Even the most meticulously cared for yacht usually smells of diesel. Placing the engine behind a watertight bulkhead really fixes this big
problem. An engine mounted in the
main cabin can heat up the living areas. This may be fine in the winter, but is a disaster in the summer.
5. Thrust. The downward
thrust of the prop at the stern of the boat helps lift the stern and prevent
it from squatting, giving a bit more speed. If the prop is near the keel, it tries to lift the entire boat. Not so good.