Mercury 40 Jet Manual page 105

OUTBOARD INSTALLATION
• Installing the outboard too high on the transom will allow the
water intake to suck in air and cause cavitation. (Cavitation
will cause the engine to overspeed in spurts and reduce
thrust.) This condition should be avoided by proper height
setting.
• Installing the outboard too low on the transom will allow
excessive drag.
BOATS WITH A "V" BOTTOM HULL
1. Measure the width of the leading edge on the water intake
housing. Make a horizontal line on the transom up from the
"V" bottom the same length as the width of the water intake
housing.
a - Horizontal line
b - Width of the leading edge on the water intake housing
2. Place (center) the outboard on the boat transom. Set the
height of the outboard on the boat transom so that the front
edge of the water intake housing is in line with the horizontal
line made in step 1. Temporarily clamp the outboard to the
transom at this position.
a
b
97
22401