Technical data

In case it is necessary to hoist the engine either front end upwards or reverse gear end upwards,
the attachment of slings must be done very carefully to avoid the possibility of damage to the parts on
which the weight may bear. It is best if special rigging work be done by someone experienced and
competent in the handling of heavy machinery.
ENGINE BOLTS
It is recommended that bronze hanger bolts of appropriate size be used through the engine
flexible mounts. Lag screws are less preferred because their hold on the wood is weakened every time
they are moved, whereas the lag bolt stays in position and the nut on top is used to tighten the engine
down or is removed to permit the engine to be lifted. The bolt itself stays in position at all times, as a
stud, and the bond between the bolt and the wood is not weakened by its removal.
FOUNDATION FOR ENGINE
A good engine bed contributes much toward
the satisfactory operation of the engine. The engine
bed must be of rigid construction and neither deflect
nor twist when subjected to the engine weight or the
position the boat may have to take under the effects
of rough seas. The bed must keep the engine within
one or two thousandths of an inch of this position at
all times. It has to withstand the forward push of the
propeller which is applied to the propeller shaft, to
the thrust washer bearing in the engine and finally to
the engine bolts and engine bed.
In fiberglass hulls, we recommend that
similar wooden stringers as in wooden hulls be
formed and fitted, then glassed to the hull securely.
This allows hanger bolts to be installed firmly in
wood, thus reducing~noise and transmitted
vibration.
The temptation to install the engine on a pair
of fiberglass "angle irons" should be resisted. Such
construction will allow engine vibrations to pass
through to the hull. Flexible mounts require a firm
foundation against which to react if they are to do their job. When possible, follow bed design "A" and
avoid bed design "B".
PROPELLER COUPLING
Each Westerbeke Diesel engine is regularly fitted with a suitable coupling connecting the
propeller shaft to the engine.
The coupling must not only transmit the power of the engine to turn the shaft, but must also
transmit the thrust either ahead or astern from the shaft to the thrust bearing which is built into the
reduction gear housing of the engine. This coupling is very carefully machined for accurate fit.