[StephenCon]

I am using a Mercury 9.9hp 2-stroke on a 23' sail boat. Currently there is a 10", 3 blade, 5.5pitch prop installed. This combination works great when operating in forward speeds. However, it provides very little torque in reverse.

Would it be adventagious to install a 4 blade prop with a slightly higer pitch to get more performance in reverse?

I was considering a 4 blade, 10" with a 7" pitch.


-Thanks

[gcboat]

First off a 9.9 on a 23 foot boat isn't going to do much going either way, especially in reverse. Besides the small amount of power you have the motor has to overcome the resistance of that flatter transom.
At least going forward the bow has a sharper entry.
As far as changing the prop is concerned I'd be a little leary of it. That's a mighty small powerplant and you're considering a rather large amount of pitch change.
Hopefully someone will come along and give you some solid advise.

[hwsiii]

If the RPM are at the upper range of your recommended WOT setting just get a 4 blade prop in the same pitch you have. It will give you more low end thrust and reverse thrust as well.


H