Yamaha F25A Owner's Manual

Also see for F25A: Service manual Owner's manual Service manual Service manual Owner's manual

Contents

30InstallationEMU26902InstallationThe information presented in this section isintended as reference only. It is not possibleto provide complete instructions for everypossible boat and motor combination. Prop-er mounting depends in part on experienceand the specific boat and motor combination.WARNINGEWM01590● Overpowering a boat could cause se-vere instability. Do not install an out-board motor with more horsepowerthan the maximum rating on the capac-ity plate of the boat. If the boat does nothave a capacity plate, consult the boatmanufacturer.● Improper mounting of the outboard mo-tor could result in hazardous condi-tions such as poor handling, loss ofcontrol, or fire hazards. For permanent-ly mounted models, your dealer or oth-er person experienced in properrigging should mount the motor.EMU33470Mounting the outboard motorThe outboard motor should be mounted sothat the boat is well balanced. Otherwise, theboat could be hard to steer. For single-en-gine boats, mount the outboard motor on thecenterline (keel line) of the boat.EMU26921Mounting heightTo run your boat at optimum efficiency, thewater resistance (drag) of the boat and out-board motor must be made as little as possi-ble. The mounting height of the outboardmotor greatly affects the water resistance. Ifthe mounting height is too high, cavitationtends to occur, thus reducing the propulsion;and if the propeller tips cut the air, the enginespeed will rise abnormally and cause the en-gine to overheat. If the mounting height is toolow, the water resistance will increase andthereby reduce engine efficiency. Mount theoutboard motor so that the anti-cavitationplate is between the bottom of the boat anda level 25 mm (1 in.) below it.1. Center line (keel line)ZMU017601