Sea Ray 270 Select EX, Руководство пользователя

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S
ECTION
4 • B
ILGE
& U
NDERWATER
G
EAR
4.4
270 Select EX
D. P
ROPELLER
S
ELECTION
IMPORTANT: Installed propeller must allow
engine to operate at its specified maximum
WOT (wide open throttle) RPM. Use an
accurate service tachometer to verify
engine operating RPM.
It is the responsibility of the boat manufacturer
and/or the selling dealer to equip the power
package with the correct propeller. Refer to
Quicksilver publication -
Everything You Need
To Know About Propellers P/N 90-8614492 .
Specified engine WOT and operating RPM
range are listed in the
Mercury MerCruiser
Operation, Maintenance and Warranty Manual
attached to the engine.
If full throttle operation is below the
recommended range, the propeller must be
changed to prevent loss of performance and
possible engine damage. On the other hand,
operating an engine above the recommended
operating RPM range will cause higher than
normal wear and/or damage.
After initial propeller selection, the following
common problems may require that the
propeller be changed to a lower pitch:
• Warmer weather and greater humidity
cause an RPM loss.
• Operating in a higher elevation causes an
RPM loss.
• Operating with increased load (additional
passengers, pulling skiers, etc.).
For better acceleration, such as is needed for
water skiing, use the next lower pitch propeller.
However, do NOT operate at full throttle when
using the lower pitch propeller but not pulling
skiers.
moving forward. There is no protection if the stern
drive is struck during reverse operation or from an
angle when moving forward.
If you strike a submerged object, STOP THE
ENGINE as soon as possible and examine the
stern drive unit for damage. Even if no damage is
visible, there could be internal problems or difficulty
maneuvering. If you must use the boat after impact,
run at the lowest speed possible.
2. E
NGINE AND
S
TERN
D
RIVE
A. M
AINTENANCE AND
S
ERVICE
Engine failure away from shore can be
dangerous.
You must follow the recommended
maintenance schedule to best ensure trouble-free
operation of your engine and stern drive.
B. V
IBRATION AND
C
AUSES
Some vibration is to be expected in your boat
because of the action of the engines and the
propeller. But excessive vibration indicates
conditions which must be promptly corrected to
avoid damage. The following are some conditions
which may cause vibrations:
• Weeds, ropes, fishing lines, nets or your own
trailing lines can become wrapped around the
propeller and/or shaft, causing vibration and loss
of speed. Always stop the boat, make sure it is
clear to the rear, and then reverse the propeller
after going through a weedy area to unwrap and
clear away any weeds which may have
accumulated. If this doesn’t clear the
entanglement, and you can’t anchor or moor the
boat in shallow water to get to the stern drive in
the water, the boat will have to be taken out of
the water.
• A badly damaged or distorted propeller or shaft
is an obvious cause of vibration. Run at slow
speed to shore. REPLACE IMMEDIATELY.
• If the engine mounts fail and the engine can
contact the hull while it is running, vibration will
be felt. Run at slow speed to shore. REPLACE
IMMEDIATELY.
C. I
MPACT TO
S
TERN
D
RIVE
The stern drive can be damaged by impact, either
while trailering or boating. To minimize the possibility
of impact damage while trailering, keep the stern
drive raised to the trailering position.
The hydraulic system used to raise and lower the
stern drive can cushion impact and lessen damage
from head-on impacts to the stern drive from
underwater objects BUT ONLY when the boat is