The "black art" of prop selection
What size is your engine? Using the standard 2 hp for every thousand pounds of displacement, the E 28 is underpowered by 5 hp. Prop is correct size and pitch...just cannot handle the 3 k current we have on the Hudson...finally changing out this winter
We have been through two fixed two blade props, one feathering two blade, and currently a fixed three blade prop, since we bought our boat in '94. The pitch was really wrong on the two blade fixed that it came with, and probably had been that way for years.
Assumptions about the correctness of the prop on your boat when you bought it, new
or used, and often unwarranted.....
Our current three bladed fixed is almost (but not quite...) perfect, and good enough for us.
For many years I thought that boats like mine would motor at about 6 to 6.5 kts. Now I know better! We routinely motor at 7. kts. While we gave up some real speed under sail for this "cruising" prop, the journey has been worthwhile to arrive at the point where we know what pitch (and number and shape of blades) really matches our hull and motor.
FWIW, a YSM-12 is a real work horse of a diesel. I have done a week-long delivery on a 33 foot sailboat with that same engine and it puts out enough torque for that boat to motor 24/7 at 6 Kt +.
There are some good threads here on prop choices. Some searching might be in order.
http://www.ericsonyachts.org/infoexchange/showthread.php?571-quot-Prop-Options-quot&referrerid=28
http://www.ericsonyachts.org/infoex...?7999-Prop-Comparisons-part-two&referrerid=28
Not an all-inclusive list, by far, but a start.
Cheers,
Loren