CORRECT CRAFT Ski Nautique, Owner'S Manual

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piston ring life. A heavy-duty thermostat is used to control the amount of
water which is discharged from the engine after the desired operating
temperature is reached. The discharged water is automatically replaced by
cool raw water from the supply side, maintaining a stable engine temperature
through an exceptionally simple system. The hot water is discharged into the
exhaust manifold water jackets.
If the engine begins to overheat, stop the boat immediately. Check the water
intake on the bottom of the boat, water strainer and the transmission oil cooler
for obstructions. Check the water pump drive belts for proper tension and
possible slippage. Look at the water lines for possible kinks.
WARNING: Removal of hoses from the engine while the boat is in the water
may allow water to enter the bilge and could sink the boat. Remove hoses only
if you have determined you can do so in complete safety.
On a Ford engine, a partial inspection of the flexible impeller of the supply
pump can be made. Remove the top hose and drive belt from the supply pump
and look into the pump chamber while slowly turning the pump pulley. A
badly damaged impeller may be detected by doing this.
If a problem is found and corrected, do not attempt to restart the engine until
it has cooled down to normal temperature. This is important to prevent engine
damage due to thermal shock.
Fresh Water Cooling
Engines manufactured with an optional fresh water cooling system are
identified with an “X” in the second position from the left in the model
identifier on the engine identification tag.
The PCM freshwater cooling system consists of two (2) sections. The raw
water section and the self contained fresh water section which is filled with a
fifty-fifty mixture of anti-freeze and water.
The coolant in the freshwater section circulates through the engine block,
heads and the intake manifold absorbing the heat created by the engine
operation. When the engine is at operating temperature, the thermostat allows
coolant to flow around the sides of the tubes in a heat exchanger where heat is
transferred to the raw water flowing through the center of the heat exchanger
tubes. The raw water is then directed into the manifolds and risers where it
mixes with the exhaust.
If your engine begins to overheat, you should inspect this heat exchanger as
well as the previously mentioned areas.
Checking Coolant Level
WARNING: Reservoir is equipped with a 14 lb. (6.35kg) pressure cap. DO
NOT remove the pressure cap when the engine is hot. This could cause
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