Thread: Prop dilemma

Originally Posted by SeaRay

Both props are 3 blade.

I strongly urge you to try a 4 blade then

If you are redlining a 3 blade 10 pitch at only 3/4 throttle, then a 4 blade 10 pitch probably would be about right.

It's either going to be a 10 pitch 4 blade, or a 9 pitch 4 blade that's going to give you optimum results.

Solas Amita 4, 9 pitch - 5113-093-09
Solas Amita 4, 10 pitch - 5113-093-10

You'll want to double-check that your motor is a 14 spline and that those will fit. Each prop is about $60, could always order both pitches and keep one as a spare, that way you know for sure exactly which one works better on your boat.

I actually have two props like this, I have a 14 pitch that I use in the summer with light loads, and then switch to the 13 in the winter for duck hunting when I tend to have a full boat of people and gear and heavier loads.

Starting by experimenting with props is a whole lot cheaper than messing with jackplates and whale tails and all that. Many times after getting the right prop on there, you end up not messing with the other stuff.

I'll check on the 10 pitch. I'm gonna be "prop poor" if this keeps up, but you are right, it is cheaper than a $600 tilt mechanism.

Originally Posted by SeaRay

I'll check on the 10 pitch. I'm gonna be "prop poor" if this keeps up, but you are right, it is cheaper than a $600 tilt mechanism.

For $60, it's worth a shot. A 4 blade on my boat made it feel like an entirely different boat when compared to when it had a 3 blade on it.

Originally Posted by artcarney_agr

For $60, it's worth a shot. A 4 blade on my boat made it feel like an entirely different boat when compared to when it had a 3 blade on it.

Just to be clear, I'm looking for more speed. The 3blade SS prop jumps on plane and runs well but it tops out at 5200PRMs which is 20-22 MPH depending on wind, load etc.
My understanding of 4blade applications was for heavy load carrying and not necessarily more speed.
So you are saying you gained more top end going to the 4 blade, correct?

Originally Posted by SeaRay

Just to be clear, I'm looking for more speed. The 3blade SS prop jumps on plane and runs well but it tops out at 5200PRMs which is 20-22 MPH depending on wind, load etc.
My understanding of 4blade applications was for heavy load carrying and not necessarily more speed.
So you are saying you gained more top end going to the 4 blade, correct?

You are correct that you won't gain more top end with light load, you might actually lose 1 mph, maybe 2 mph due to the added surface area of the prop...but you gain top speed with more load/passengers.

If you were getting 23 mph solo with a 3 blade, you might only get 22 solo with the 4 blade...you said you were getting 20 with a passenger with the 3 blade, well with the 4 blade you'd be getting about 21 or 22 with a passenger. Your gains on top end are higher with more load.

Just as an example, with my boat, I have a 17 ft with 40 hp - I had a 3 blade 15 pitch prop, it worked fine with just me in the boat and I could do about 24 mph...now with the 4 blade 13 pitch I get about 23 mph solo and the improved handling and performance more than makes up for the 1 mph loss on top end, the gain in rough water where I can maintain higher speed and better control than ever before is huge. With the 3 blade, when I added 1 passenger, top end would drop to about 20 mph and took forever to get on plane, with 2 passengers I was lucky to get on plane and had to have passengers move to the bow for it to even plane, and with 3 passengers I never got on plane. Now with a 4 blade 13, I can get on plane with 3 passengers and run 20 mph whereas before I could never get on plane (about 7 mph with the motor pegged, I was like a barge), so that was a jump from 7 mph to 20 mph which is huge.

If gaining top end while solo is your only goal, then finding a 3 blade with higher pitch is what you'll need to do, but you're going to kill performance with a passenger and cripple yourself when the water gets rough. Sure you can add a jackplate to gain more top end but with a small motor and boat you'll spend a fortune to only gain 1 to 2 mph, the cost for such little gain is simply crazy but to each his own. I did add a jackplate to my boat, but it wasn't for top end gain, it was for the breakaway feature of the CMC BA-130 because I run in a lot of shallow water with stumps...the BA-130 is also called a kick-up plate...I gained 1 mph on top end when solo, and there was no change on top end with 1 or more passengers. If you're seriously considering spending $600+ for jackplate with tilt and trim to gain only 1 to 2 mph when solo, you'd be much better off simply selling your 20 hp motor and upgrading to a motor with more horsepower.