Mercury 92-858058K01, Manual, Page: 36 / 150

Section 3 - On the Water
Page 28 90-879172181
eng
FEBRUARY 2011
!
WARNING
Operating a boat with impact damage can result in product damage, serious injury, or death. If the boat experiences an impact,
have an Authorized Cummins MerCruiser Diesel Repair Facility inspect the vessel and power package and perform repairs as
necessary.
Operating with damaged underwater drive components or boat bottom could cause additional damage to other parts of the power
package, or could affect control of the boat. If continued operation is necessary, do so at greatly reduced speeds.
Zeus Drive Impact Protection
IMPORTANT: Although the design of the Zeus drive provides some impact protection, no design can ensure total protection from
impact damage under all conditions.
The Zeus drive has some impact protection by design, since the drive is mounted in a tunnel above the bottom of the hull. If the
drive strikes a floating or submerged object while the boat is moving, the skeg is designed to break away, absorbing some of the
impact and possibly reducing damage to the propellers and the exposed lower part of the drive. In extreme cases, large fixed or
floating objects struck by the skeg and the exposed lower part of the drive may cause the lower part of the drive to shear off. This
shearing off of the lower part of the drive is a design feature to protect the hull and drive system.
NOTE: If the lower part of the drive shears off due to a severe impact, make immediate note of the GPS location to assist in
recovery efforts. If recovery of the damaged parts of the drive is possible, return the damaged parts to your Authorized Cummins
MerCruiser Diesel Repair Facility for possible repair and reuse.
If an impact occurs and damage is present or suspected, if the boat does not respond as it should, or if water is present in the
gear lube monitor bottle, have your boat inspected at the nearest Authorized Cummins MerCruiser Diesel Repair Facility.
Operating in reverse gear offers less impact protection. Use extreme caution when operating in shallow water or where underwater
objects are known to be present. Use extreme care to prevent striking submerged objects while operating in reverse.
Zeus Drive Alignment
The Zeus Drives are aligned by the boat manufacturer, and must not be adjusted by anyone other than your Cummins MerCruiser
Diesel Authorized Service and Repair Facility. The Zeus drives automatically recalibrate to this setting at each startup. The drives
do not need to be re‑aligned under normal use.
Conditions Affecting Boat Operation
Weight Distribution (Passengers and Gear) Inside the Boat
Shifting weight to the rear (stern):
•
Causes the bow to bounce in choppy water.
• Increases the danger of a following wave splashing into the boat when coming off plane.
• Can cause the boat to porpoise at extremes.
Shifting weight to the front (bow):
•
Improves ease of planing.
• Improves rough water ride.
• Can cause the boat to veer back and forth (bow steer) at extremes.
Bottom Of Boat
To maintain maximum speed, the boat bottom should be:
•
Clean and free of barnacles and marine growth.
• Straight and smooth (fore and aft).
Marine vegetation can accumulate when the boat is docked. Remove this growth before operation; it can clog the water inlets and
outlets, causing the engine to overheat.
Cavitation
Cavitation occurs when water flow cannot follow the contour of a fast‑moving underwater object, such as a gear housing or a
propeller. Cavitation increases propeller speed while reducing boat speed. Cavitation can seriously erode the surface of the gear
housing or the propeller. Common causes of cavitation are:
•
Weeds or other debris snagged on the propeller
• Bent propeller blade
• Raised burrs or sharp edges on the propeller