T&T: Propeller question...

[Peter Bennett]

As my boat recently broke its propeller shaft (close to the prop), I
now have the opportunity (?) to purchase a new prop.

The prop that is now lying somewhere on the bottom of Howe Sound was a
4 blade.  The boat also came with a 3 blade prop as a spare.  The 3
blade is now installed on the boat, and I wonder if I should get a 4
blade or another 3 blade (or something else?), as a spare.

The boat is 31 ft, and has a single Cummins 6BTA5.9 engine.

Are there any good reasons for choosing a 4 blade over 3, or vice
versa? Any recommended suppliers in the PNW? (The fellow who installed
the new shaft and prop suggests getting a new prop from the US, as he
says the Vancouver shops are too expensive.)
  

-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Ennos 31 "Honeycomb"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca