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The old two-blade folding prop might have given the boat another half a knot under some conditions when the engine was turned off but I really don't see any drag with the new one - and I always put the gearbox in astern when the engine's turned off to minimize wear on the transmission. However, what I do see is much more torque in bad conditions, more speed under power and greatly increased response and handling ability under all conditions. I also (with the help of Lucky Mike) replaced the old propeller shaft, the seal and the cutlass bearing. The old prop shaft had somehow sucked a short piece of wire into the stuffing and the shaft was fairly badly pitted. The new seal is a Packless Sealing System - a mechanical shaft seal is created by the contact of a turning surface against a stationary surface. The stationary surface is a carbon flange held in contact against a stainless steel rotor which turns with the shaft. The carbon flange is attached to the boat by a nitrile bellow which, with the help of water pressure, produces a constant contact between the carbon and the stainless steel ring. These type of seals are unaffected by engine motion or vibrations and are well proven. The result is a 100% watertight and totally maintenance-free shaft seal.
The prop is 15" by 11° - the pitch and size determined by a software program that requires hull type, engine horse power, maximum and cruising RPM and true displacement weight.
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finngulf 391