Table of Contents
Advertisement
Section 3 - On the Water
Shifting weight to front (bow):
•
Improves ease of planing
•
Improves rough water ride
•
At extremes, can cause the boat to veer back and forth (bow steer)
Bottom of Boat
To maintain maximum speed, ensure that the boat bottom is:
•
Clean, free of barnacles and marine growth.
•
Free of distortion, nearly flat where it contacts water.
•
Straight and smooth, fore and aft.
Marine vegetation may accumulate when the boat is docked. This growth must be removed before operation; it may clog water
inlets and cause the engine to overheat.
Elevation and Climate
NOTE: Engines equipped with an Engine Control Module (ECM) reduce the effects of changes in elevation and climate by
automatically adjusting fuel flow for weather conditions and elevation. ECM controlled engines, however, do not compensate for
increased loading or hull conditions.
Elevation and climate changes affect the performance of your power package. Loss of performance can be caused by:
•
High elevations
•
High temperatures
•
Low barometric pressures
•
High humidity
For optimum engine performance under changing weather conditions and high elevation, use a propeller that allows the engine
to operate at rated RPM at wide open throttle (WOT) with a maximum boat load during your normal boating.
In most cases, the rated RPM at WOT can be achieved by changing to a lower pitch propeller.
Propeller Selection
Operating the engine with the wrong propeller installed can limit power, increase fuel consumption, overheat the engine, or
cause internal powerhead damage. Choose a propeller that allows the engine to operate at the specified wide open throttle
RPM.
The boat manufacturer and the selling dealer are responsible for equipping the power package with the correct propellers.
IMPORTANT: The engines covered in this manual are equipped with an ECM that limits engine RPM. Be sure that the propeller
being used does not allow the engine to run against the limiter, as a significant loss in performance will result.
NOTE: Use an accurate service tachometer to verify RPM.
Select a propeller that will allow the engine power package to operate at the rated engine RPM with a maximum load.
If full throttle operation is below the engine rated RPM, the propeller must be changed to prevent loss of performance and
possible engine damage. On the other hand, operating an engine above the rated engine RPM will cause higher than normal
wear or damage.
After initial propeller selection, the following common problems may require that the propeller be changed to a lower pitch:
•
Warmer weather and greater humidity cause an RPM loss (not as significant on these models).
•
Operating in a higher elevation causes an RPM loss (not as significant on these models).
•
Operating with a damaged propeller or dirty boat bottom causes an RPM loss.
•
Operating with increased load (additional passengers, pulling skiers).
For better acceleration, such as is needed for water skiing, use the next lower pitch propeller. Do not operate at full throttle
when using the lower pitch propeller but not pulling skiers.
Getting Started
Initial Break‑In Procedure
It is important to follow this procedure to properly break in the engine.
IMPORTANT: Mercury Marine recommends that the boat not be accelerated hard until this procedure has been completed.
Page 28
NOTICE
90-8M0069748
APRIL 2012
eng
Advertisement
Table of Contents
Troubleshooting
