Breaking In Engine - Yamaha Z300 Owner's Manual

1. Center line (keel line)
EMU26930
Mounting height (boat bottom)
To run your boat at optimum efficiency, the
water resistance (drag) of the boat and out-
board motor must be made as little as possi-
ble. The mounting height of the outboard
motor greatly affects the water resistance. If
the mounting height is too high, cavitation
tends to occur, thus reducing the propulsion;
and if the propeller tips cut the air, the engine
speed will rise abnormally and cause the en-
gine to overheat. If the mounting height is too
low, the water resistance will increase and
thereby reduce engine efficiency. Mount the
outboard motor so that the anti-cavitation
plate is in alignment with the bottom of the
boat.
NOTE:
The optimum mounting height of the out-
G
board motor is affected by the boat/motor
combination and the desired use. Test
runs at different heights can help deter-
mine the optimum mounting height. Con-
sult
manufacturer for further information on de-
termining the proper mounting height.
For instructions on setting the trim angle of
G
the outboard motor, see page 47.
EMU27041
Your new engine requires a period of break-
in to allow mating surfaces of moving parts to
wear in evenly. Correct break-in will help en-
sure proper performance and longer engine
life.
ECM00750
CAUTION:
Failure to follow the break-in procedure
G
could result in reduced engine life or
even severe engine damage.
Do not use premixed fuel in this engine
G
because it could cause carbon depos-
its on the fuel injector and engine trou-
ble.
Follow the instructions for break-in
G
carefully.
NOTE:
Leave the label pictured below on the top
cowling until the break-in procedure has
been completed. It may be removed after-
wards.
ZMU01762
Operation
your Yamaha dealer

Breaking in engine

or boat
37