Four winns V458, Owner'S Manual

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Owner’s Manual Page 55 Engines, Drives and Instrumentation - Section E
Consult the engine operator’s manual and the oil
pump manufacturer’s manual provided in the owner’s
packet for specific information.
Figure E1: Oil Change Pump
B. Volvo Penta IPS Drive-Units
The Volvo Penta Inboard Performance System (IPS)
has twin drive-units that are steerable. These drive-
units turn and point the entire thrust in the desired
direction. The drive-units can be steered independent-
ly of one another. Each drive-unit is coupled to its
respective diesel engine and shifting is performed
with-in the drive-unit. The drive-units are mounted
through the hull at the stern. This type of system is
depicted in Figure E2.
Figure E2: Volvo Pents IPS Drive-Unit
NOTICE
To go from FORWARD to REVERSE, or
REVERSE to FORWARD; always pause at
NEUTRAL and allow engine speed to return to
idle. NEVER shift the unit while engine speed
is above 1500 rpm.
E - 4 PROPELLERS
Knowledge of the propeller is most easily gained
through better understanding of the terminology
used to refer to the aspects of propeller size and
performance. It should be noted the V458 models
include two counter-rotating Nibral propellers on each
propulsion unit..
A. Diameter
Diameter is twice the distance from the center of
the prop shaft to the extreme tip of a propeller blade.
Increasing or decreasing propeller size will have a
direct bearing on the RPM’s an engine will develop.
This is due to the greater amount of propeller blade
surface in contact with the water. See Figure E3.
Figure E3: Propeller Pitch & Diameter
B. Pitch
Pitch is a measure of helix angle, or angle of attack,
of the rotating blade. Pitch is easily under stood if one
imagines the propeller rotating through a semisolid
such as butter or gelatin. The distance the propeller
will travel in one revolu tion is called “Pitch.” Increasing
or decreasing pitch will also have a direct bearing on
engine RPM’s because of the greater bite taken by
the blade with each rotation. See Figure E3.
Oil Change Pump
Battery Lid
Bow