Operation

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 engine 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.

ZMU01762

NOTE:

●The optimum mounting height of the out- 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 your Yamaha dealer or boat manufacturer for further information on de- termining the proper mounting height.

●For instructions on setting the trim angle of the outboard motor, see page 34.

EMU27020

Breaking in engine

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 ensure proper performance and longer engine

life.

ECM00140

CAUTION:

●Failure to follow the break-in procedure could result in reduced engine life or even severe engine damage.

●Premix fuel must be used during break- in in addition to oil in the oil injection system.

EMU27060

Gasoline and engine oil mixing chart (50:1)

1.: Engine oil

2.: Gasoline

ECM00150

CAUTION:

Be sure to mix gasoline and oil complete- ly, otherwise the engine may be dam- aged.

EMU30311

Procedure for oil injection models

Run the engine under load (in gear with a propeller installed) for 10 hours as follows.

1.First 10 minutes:

Run the engine at the lowest possible speed. A fast idle in neutral is best.

2.Next 50 minutes:

Do not exceed half throttle (approxi- mately 3000 r/min). Vary engine speed occasionally. If you have an easy-plan- ing boat, accelerate at full throttle onto plane, then immediately reduce the

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