Short Wave Sportfishing wrote:

On Mon, 25 Dec 2006 19:25:38 -0500, Gary KW4Z
wrote:


The boat that I purchased had the original prop stolen and I am going to
have to replace it. It's an 18ft Pro Tournament Sprint boat that has an
Evinrude 175 HP motor. The original prop was a three blade stainless.

I've looked at a site online to find props but when I put in the information
it list 16 different pitches from 10" to 28" pitch. Additionally there are
four blade models and three blade. I believe, from what I'm told, the
original prop was a three blade stainless.

Can anyone tell me how to determine what Pitch I should be looking for?
What about three or four blades and the advantages of each? Either that or
I'd appreciate if you know any good web site URL's that would help teach me
what I need to know before making the wrong decisions.


Depending on the year (again), a 14.25" x 21p is the most likely prop
for that boat and engine - maybe even a 23p. Again, depends on the
year, weight of the boat, etc.

As to SS, it will be pricey - probably in the $600 plus/minus $50
range.

With respect to three/four blade, I'm four square in the four blade
camp. I changed from a three blade 14.25 x 19 three to a 14.25 x four
blade with my E-TEC and the difference was flat out amazing. Plenty
of bite, acceleration up the wazoo, never cavitates even in extreme
operating conditions - simple amazing difference from the old four
blade. With the three blade, my Ranger never had any bow lift - it
accelerated flat to the water and once on plane, would jump in rpm
from 3 grand to 4 grand - the four blade, I got lots of bow lift, the
acceleration is smooth as silk and operating bite when it's trimmed
out - no cavitation.

Go with the four blade.

I bought a four blade for my center console hoping for the same results
as yours. The performance was worse than my factory aluminum three
blade so I bought a stainless three blade to replace it. Still
unsatisfied with the WOT RPM's, I handed it to a prop shop and they gave
it a cup. Now it works perfectly. Sizing props is a huge guessing game
but if you get close a good prop shop can tweak it for a lot less than a
new one. My four blade is now running great on my friend's 20' aluminum
walleye boat with a 125 Merc.

Dan

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