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The Jet must be submerged at least up to boat
propulsion the Jet driveshaft to prime when the vessel isstationary.For
vessels with low transom emerson, modifications to the hull may benecessary.·
A deadriseboat
propulsionof a minimum of 8° is recommended at the
transom to avoidboat
propulsionair enteringthe Jet intake.· Appendages
such asboat
propulsionkeels/strakes should be kept clear in front of
the Jet intake, inorder to stop possible cavitation. (Refer Pacific Jets
for the correct distance as thisdistanceboat
propulsionwill vary depending
on Jet Model selected).The basicboat
propulsioninformation required
to select a TWIN DISC JETS Jet to match an engine and vessel iscontained
in the APPLICATION CHECKLIST.Once this information is available it is
possible to select an appropriate Jet Model (or multiple of
Jets).Each Jet Model has maximum recommended displacementsboat
propulsionat maximum power inputs. This issummarized in the JET SELECTION - BY DISPLACEMENT
table.boat
propulsionTHESE SELECTION TABLES are a guide only and utilize
only one factor in the selectionprocess (DISPLACEMENT). Other factors
including waterline length, engine selection,hull shapeboat
propulsionand intended usage influence the final Jet selection for optimum propulsiveefficiencies.2.
Tables assume that the hull shape selected is suitable for the intended
use and speed.The Jet is installed correctly and thereboat
propulsionare no keels, appendages or aeration.3. Laden displacements listed in
the table are MAXIMUM. Displacements well below themaximum All Up Weight
(A.U.W.) are required for best propulsive efficiency.4. A.U.W, in the
grey area will generally result in reduced propulsive efficiencyboat
propulsionand mayhave application restrictions.5. Table assumes that
the trim of the vessel is optimised for the intended use and speed. ALL
APPLICATIONS MUST BE CHECKED BY TWINboat
propulsionDISC APPLICATION
DEPARTMENTS PRIORboat
propulsionTO ORDER OR CONSTRUCTION, ESPECIALLY
APPLICATIONS WHICH FALL IN THE SHADED DISPLACEMENT AREAS The Speed Guide
Table relates powerboat
propulsionto weight ratios (HP/Tonne)boat
propulsionfor a given WATERLINE LENGTH (W.L.L.) to boat speed. With a known engine
HP, the A.U.W. of the vessel and the W.L.L., plot aboat
propulsionvertical
line from the W.L.L. to the HP/tonne curve and draw a horizontal lineboat
propulsionto read off the boat speed (knots). If the engine power
is not selected, but W.L.L. and expected boat speed areboat
propulsionknown, plot a horizontal and vertical line, and their intersection will
give the required power to weight ratio(HP/tonne).Once the required power
to weight ratio (HP/tonne) is established fromboat
propulsionthe Speed
Guideboat
propulsionTable, thetotal power requirement is obtained by:For
multiple Jet installationsvdivide total power by the number of Jets to
give the power outputrequired per engine.Select anboat
propulsionengine
HP, atboat
propulsionleast equal to or greater than that required from
the Speed Guide Table.Theboat
propulsion.
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