PURSUIT OS 315, Owner'S Manual

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OS 315
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1.5 Propellers
The propellers convert the engine’s power into thrust. They come in a variety of styles, diameters and pitches.
The one that will best suit the needs of your Pursuit 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 (example 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 Engine Instrumentation
The helm station is equipped with a set of engine instruments and alarms. These instruments allow the operator
to monitor the engines’ operational conditions. Close observation of these instruments allows the operator
to operate the engines at the most efficient level and could save them from serious costly damage. The
instrumentation is unique to the type of outboard motors installed on your Pursuit. Some or all of the following
gauges may be present.
This model may be equipped with Yamaha Command Link Integrated Information System®. Please
refer to the Yamaha manuals for information on the operation of this system.
TACHOMETER
The tachometer displays the speed of the engine in revolutions per minute (RPM). This speed is not the boat
speed or necessarily the speed of the propeller. The tachometer may not register zero with the key in the “OFF”
position.
NEVER EXCEED THE MAXIMUM RECOMMENDED OPERATION RPM OF THE ENGINE.
MAINTAINING MAXIMUM, OR CLOSE TO MAXIMUM, RPM FOR EXTENDED PERIODS
CAN REDUCE THE LIFE OF THE ENGINE.
SPEEDOMETER
The speedometer indicates the speed of the boat in miles per hour. Most speedometers measure the water
pressure against a small hole in a pickup tube located in the engine lower unit or mounted on the bottom of
the transom.
TEMPERATURE WARNING
The temperature warning indicates the temperature of the engine. A sudden increase in the temperature could
indicate an obstructed water inlet or an impeller failure.
CONTINUED OPERATION OF AN OVERHEATED ENGINE CAN RESULT IN ENGINE SEI-
ZURE. IF AN UNUSUALLY HIGH TEMPERATURE READING OCCURS, SHUT THE EN-
GINE OFF IMMEDIATELY. THEN INVESTIGATE AND CORRECT THE PROBLEM.