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  Martec solves the problem of feathering propellers for racing and cruising with its Autostream® three blade feathering propellers. The Autostream® is the logical and performance alternative for both moderate and heavier displacement sailboats; particularly for hulls with either a modified fin or full keel. And when compared to a fixed prop, the Autostream® significantly reduces drag while improving reverse performance. The three-blade model is also available for "Saildrive" engine installations and may be fitted to Volvo, Yanmar or Bukh saildrives. The Saildrive models' unique fail-proof cushion hubs absorb shock. And unlike other types of propellers, they cannot fail and leave you without drive.
  The large blade area of the Autostream® and the ability to easily adjust the pitch allows the propeller to be "fine tuned." With tuning, the Autostream can optimize both performance and fuel consumption to achieve efficiencies comparable to that of the appropriate fixed blade propeller. For flexibility, stainless model Autostream Propellers may be assembled in either a right or left hand configuration. Now combine this with the capability of making precise pitch adjustments to the same propeller. This means that you may still use your Autostream® feathering propeller with a replacement engine, even when the propeller shaft rotation changes direction.
REVERSE THRUST   Excellent backing down characteristics are the hallmarks of the Autostream® propellers. They are among the most effective feathering propellers designed for changing from forward to reverse. Autostreams® rotate their blades 180 degrees on their axes in less than one shaft revolution. The propeller presents the same leading edge of the blade in both directions. The result: extraordinary reverse performance when compared to folding, fixed blade and even self-pitching propellers. In most installations the Autostream® equipped yacht can stop within it's own length from speeds of six knots or more in emergency situations. And unlike some feathering propellers requiring "factory-authorized" adjustments, the reverse pitch can be owner-set to allow for the precise adjustment necessary to reduce prop walk.
DRAG   No expensive shaft lock is required to be fitted with an Autostream®. The propeller feathers itself and stays in the feathered position until rotated by the engine. This results in very low drag. even in light winds, when it is most noticeable.
  We investment cast the standard Autostream body from 316L stainless steel. The main gear and blades are fabricated from high-strength grade 2507 super duplex stainless steel, allowing us to create substantially thinner, symmetrical blade sections that are virtually flat minimizing drag and turbulence over the rudder. All components are carefully engineered for maximum corrosion protection. Larger gears provide increased reliability and strength. Instant forward and reverse adjustment by external screws means no haulout to dismantle the prop. Lubrication is through a zerk fitting. Easily changed Delrin® bearings provide many years of service life while eliminating expensive rebuilds. O-ring seals on gears and blades prevent loss of grease, while each blade has two bearings for maximum rigidity and increased bearing life. Even the easily replaced zinc anode (with a stainless core) is designed to reduce turbulence.
FEATURES   . Constructed of 316L and 2507 super duplex grade stainless steel, adds greater strength and durability over bronze propellers.
  . Delrun bearing at all the wear points allow easy and inexpensive rebuilding, eliminating wear on expensive metal surfaces.  Bearing life is 10 years +
  . Separate forward and reverse pitch adjustment allows you to set the optimum pitch in both directions. By using a simple pitch screw and locknut adjustments may be easily performed underwater, eliminating expensive haulouts
  . Superior reverse over any other propeller fixed, folding or feathering propeller.
  . Single perminent grease fitting for easy lubrication, in or out of water, for the entire propeller
  . (1) Nut sacrificial anode with stainless steel core, makes for easy replacement, and eliminates the possibility of zinc becoming dismounted.
  . For added security the assembly screws are lockwired to maintain position.
  . Propeller sizes 15"-22" (380-508mm) diameter
    . Shaft sizes to 1 1/2" (40mm) diameter
    . Five year warranty
      Check price & availability of Autostream feathering propellers
      Installation instructions
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