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 between the bottom of the boat and a level 25 mm (1 in.) below it.

0–25mm

(0–1in.)ZMU02011

NOTE:

The optimum mounting height of the out- board motor is affected by the boat and motor combination and the desired use. Test runs at different heights can help de- termine the optimum mounting height. Consult your Yamaha dealer or boat man- ufacturer for further information on deter- mining the proper mounting height.

For instructions on setting the trim angle of the outboard motor, see page 27.

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Clamping the outboard motor

1.Place the outboard motor on the tran- som so that it is positioned as close to the center as possible. Tighten the tran- som clamp screws evenly and securely. Occasionally check the clamp screws for tightness during operation of the out- board motor because they could be-

come loose due to engine vibration.

EWM00640

WARNING

Loose clamp screws could allow the outboard motor to fall off or move on the transom. This could cause loss of control and serious injury. Make sure the transom screws are tightened securely. Occasionally check the screws for tightness during operation.

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2.If the engine restraint cable attachment is equipped on your engine, an engine restraint cable or chain should be used. Attach one end to the engine restraint cable attachment and the other to a se- cure mounting point on the boat. Other- wise the engine could be completely lost if it accidentally falls off the transom.

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3.Secure the clamp bracket to the transom using the bolts provided with the out-

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