C. Prop Slip
NOTICE
Should it be necessary to change propellers,
always use an appropriate propeller removal
tool or “Prop Puller.” DO NOT attempt removal
using a hammer. Damage to the propeller or
propeller shaft can result.
When traveling through water a propeller is unable to
get a complete bite because of the fluidity of water.
“Prop slip” is usually expressed as a per cent of the
computed theoretical speed. Twenty -five to thirty-five
percent prop slip is common for a cruiser-type boat
operating at cruising speed.
Be sure the propellers are of the correct blade con-
figuration, diame ter, pitch, and shaft size to assure
good performance. For additional information on
factors affecting performance and/or assistance with
your selection, please consult your Four Winns dealer.
Changing either diameter or pitch will have an effect
on engine speed and prop slip, and in turn, directly
effect the performance of a boat. The propellers
included with each Four Winns boat provide the best
®
general performance based on data obtained from
on-the-water testing of that model. Variations in load,
operating conditions, environment, the individual
engine and hull performance may necessitate the
purchase and use of another propeller(s).
E - 5 COOLING SYSTEMS
A. Fresh Water Cooling System
Under your normal load conditions, the engines
should turn within the maximum RPM range when at
full throttle. If the engines exceed the recommended
RPM, an increase in pitch or diameter is required.
If the engine RPM is too low, a decrease in pitch or
diameter is required.
The fresh water system is the engines’ internal cooling
system. The freshwater cooling system ensures the
engine operates at the correct temperature. It is a
“closed water cooling” system and must be filled with
a mixture of at least 40% concentrated coolant and
60%
water to protect against internal corrosion,
The load carried in a boat will directly affect perfor-
mance of the engine. If an engine that is not develop-
ing full power, be sure the engine is properly tuned
and load conditions are those normally experienced,
before changing propellers.
cavitation and damage caused by freezing. This
system provides adequate engine cooling without
exposing the internal engine to the detrimental effects
of surface water, including salt, highly polluted or silt-
laden water. The engine owners manual provides
additional information regarding service and mainte-
nance of this equipment. See your Four Winns dealer
for availability.
For shipping reasons, the propellers are not factory
installed. Initial installation of the propellers will be
performed by the dealer during pre-delivery service.
Consult your specific engine manufacturer’s owner’s
manual for propeller installation instructions.
See Figure E4.
Should an engine intake or an exhaust or
cooling hose rupture, turn the engine off and
close the seacock immediately. Proceed under
tow, if necessary, to a service facility for
appropriate repairs; maintain a close visual
watch on the problem hose and also on the
bilge water level.
Straight Forward Position
Front Propeller
B. Seawater Cooling System
The seawater system is the boat’s external cooling
system. Surface water is used a cooling medium for
the control system oil cooler, fuel cooler, intercooler,
engine oil cooler and heat exchanger. The cooling
water employed enters the system through a water
intake on the drive-unit and is relinquished through the
exhaust pipe elbow where it is mixed with the exhaust
gases. Some boating areas require that additional
Rear Propeller
Figure E4: Counter-Rotating Propellers
Engines, Drives and Instrumentation - Section E
Owner’s Manual Page 56
| Categories | Four Winns Manuals, Four Winns V-Series Manuals |
|---|---|
| Tags | Four Winns V475 |
| Model Year | 2011 |
| Download File |
|
| Document Type | Owner's Manual |
| Language | English |
| Product Brand | Boats and Cruisers, Four Winns. For support contact your dealer at http://www.fourwinns.com/locate-dealer.aspx |
| Document File Type | |
| Publisher | fourwinns.com |
| Wikipedia's Page | Outboard Marine Corporation |
| Copyright | Attribution Non-commercial |
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