REVIEWED BY CAPT. MIKE SCHOONVELD
This is an idea which is either really revolutionary or completely useless. Which side you fall on depends on how and where you use your boat.
Most outboards and sterndrive boats come factory equipped with an aluminum propeller. They work pretty good and aren’t priced as though they are gold plated when compared to stainless steel propellers. Aluminum props have one side benefit or drawback (again depending on how and where you use the boat). Aluminum is a much softer metal than the stainless steel from which propeller shafts are made.
The drawback? Hit a rock, a good hard tree stump or the concrete on a boat ramp with an aluminum prop and the propeller will show it. If you are lucky, one or more of the blades will be slightly bent; less lucky, one or more of the blades will be chipped; even less lucky and there will be chunks missing from the blades and the prop so out of balance you’ll be lucky to be able to run the boat at much more than idle speed.
The good news is it’s highly unlikely the prop-shaft on your lower unit will be broken. The relative soft aluminum will chip or bend long before the shaft will be damaged. An aluminum propeller can be repaired or replaced for much less than the cost of replacing the propeller shaft.
A popular alternative for people who operate in areas where whanging a boat’s propellor into a rock, stump or other obstruction is commonplace is to swap the aluminum propeller for a stainless steel model. These don’t come cheap but the stainless blades will definitely stand up to much more abuse than those on an aluminum prop.
Being tough and strong is fine until the blade impacts something so hard (or so often) the propeller shaft gets twisted or breaks – or perhaps some other gear explodes up inside that mystical box called the lower unit. I ruined many aluminum props until I switched to stainless and have broken broken prop shafts and gears since switching to a stainless steel propeller. Here comes the Piranha Propellor.
The Piranha looks as though it’s made of black plastic, but it’s actually made of a a hard, composite material, so only partially plastic, partially resin, partially who knows? The hub part of the propeller is actually made of an aluminum core, over molded with their resin/plastic/ composite material. The hub guaranteed for life.
The hub is guaranteed to never break because the blades will. Whang into a stump, floating log, submerged rock or some other hard object and the composite blades will break off. Here’s the deal, however. The composite blades are easily replaceable and only cost $10 each, give or take a buck depending on the size. Hit something hard? Tilt up the motor and in a couple minutes, the damaged/broken blade or blades can be swapped out and everything down there is good as new.
I installed one on my boat and took it out for a test. I noticed no difference in performance between the Piranha Prop and the stainless steel propeller I normally use. Available in three and four blade models for motors from six to 280 horsepower. Check out http://www.piranha.com for prices, dealers and on-line retailers.