Scout Boats 295 Abaco, Owner'S Manual

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1.3 Engine Lubrication
2-cycle outboard motors are lubricated by a variable ratio oil
injection system. The oil tanks are mounted below the cockpit
floor near the transom.
Always monitor the oil level before each cruise by checking
the gauge or indicator lights in the helm (not available on all
engine installations) or visually checking the oil level using
the reference marks on the tank.
When additional oil is needed, use only the type of oil speci-
fied by the engine manufacturer. Refer to the engine owner’s
manual for oil specifications and additional information on the
oil injection system.
Note: Always monitor the oil level in the tank and only
use the type of oil specified by the engine manu-
facturer. Yamaha engines specify Yamalube engine
oil.
4-cycle outboard engines have an oil sump in the crankcase
that must be kept full of the type and grade of oil recommended
by the engine manufacturer. It is normal for 4-cycle engines
to consume a small amount of oil. Therefore, the oil must
be checked before each use and changed at regular intervals
as instructed by the engine owner’s manual. As with 2-cycle
engines, use only the type of oil specified by the engine manu-
facturer.
1.4 Engine Cooling System
Outboard engines are raw water (seawater) cooled. Water is
pumped through the water inlets, circulated through the engine
block, and relinquished with the exhaust gases through the
propeller hub. The water pump uses a small impeller made of
synthetic rubber. The impeller and water pump cannot run dry
for more than a few seconds. In most outboard motors, some
cooling water is diverted through ports below the engine cowl-
ing. This allows the operator to visually check the operation of
the cooling system. When the engine is started, always check
for a steady stream of water coming out of those ports.
NEVER RUN AN OUTBOARD MOTOR WITHOUT
WATER FLOWING TO THE WATER PUMP. SERIOUS
DAMAGE TO THE WATER IMPELLER OR ENGINE
COULD RESULT.
Note: If the boat is used in salt or badly polluted water,
the engines should be flushed after each use. Refer
to the engine owner’s manual for the proper engine
flushing procedure.
1.5 Propellers
The propellers convert the engine’s power into thrust. They
come in a variety of styles, diameters and pitches. All boats
powered by Yamaha engines are equipped with Yamaha pro-
pellers. The one that will best suit the needs of your boat will
depend somewhat on your application and expected average
load. Propeller sizes are identified by two numbers stamped
on the prop in sequence. The 1st number in the sequence (ex-
ample 14
” x 21”) is the diameter of the propeller, and the 2nd
number is the pitch. Pitch is the theoretical distance traveled
by the propeller in each revolution.
Always repair or replace a propeller immediately if it has been
damaged. A damaged and therefore out of balance propeller
can cause vibration that can be felt in the boat and could damage
the engine gear assembly. Refer to the engine owner’s manual
for information on propeller removal and installation.
1.6 Performance Issues and
Propellers
It is extremely important that the boat is propped to run at or
very near the recommended top RPM with an average load.
If the top RPM is above or below the recommend range, the
propellers must be changed to prevent loss of performance
and possible engine damage.
Your boat is equipped from the factory with counter rotating
engines that are mounted to achieve quicker planning and
optimum performance. Therefore, the left rotation engine is
mounted on the port side of the transom and the right rotation
engine is mounted on the starboard side. You should make
sure that each propeller matches the rotation of the engine.
Typical Engine Oil Tank