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Maneuvers of this nature could cause serious injury or death, as 
well as damage to your MasterCraft boat that will not be covered 
under warranty.
 
Boat operators should never attempt to duplicate operational skills 
of professional drivers. When such maneuvers fail, it can result in 
serious injury or death. 
 
For the best engine performance and longevity, the wide-open-
throttle (WOT) engine operation must be near the top of, but within, 
the specified WOT operating range. To adjust the WOT operating 
range, select a propeller with the proper diameter and pitch. The 
propeller supplied on the boat was chosen for best all-around per-
formance under average operating conditions.
Load, weather, altitude and boat condition all aect WOT engine 
operation. If the boat is used for several dierent applications such 
as  wakeboarding, barefooting and cruising, it may be necessary to 
have two (2) or more propellers of diering size and pitch to allow 
the engine to operate in the WOT range for each application.
Propping the boat should be done after the boat is loaded in the 
manner in which it would normally be loaded for each application. For 
example, in propping the boat for wakeboarding, fill the ballast tanks 
and add the people and gear that normally would be expected
in the boat. Take the boat out and after warm-up, run it at wide-
open-throttle and note the maximum RPM. EFI engines are 
equipped with RPM limiters to prevent over-revving. Take note if the 
RPM limiter is activated.
If the WOT RPM is higher than the maximum RPM in your engine’s 
WOT operating range, the boat is under-propped. Installing a high-
er-pitched propeller will reduce the WOT RPMs. An engine that is 
over-revving may quickly experience catastrophic damage, which 
will not be covered under warranty.
If the WOT RPM is lower than the minimum RPM in your engine’s 
WOT operating range, the boat is over-propped. Installing a lower-
pitched propeller will increase WOT RPMs.
An engine that is under-revving is “lugging.” This places a tremen-
dous load on the pistons, crankshaft and bearings and can cause 
detonation, piston seizure and other engine damage, which will not 
be covered under warranty.
 
 
 
Engines should always be operated within engine manufacturer 
guide lines. Failure to do so may cause significant damage to the 
engine and drive train and is not covered under warranty! 
 
Elevation and weather also have a very noticeable eect on the 
wide open throttle power of an engine. Since oxygen gets thinner as 
elevation increases, the engine begins to starve for air.
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