Testing new prop, Puzzling results, Need advice.

[pagick]

Originally Posted by Locozodiac

Was the sib correctly inflated to factory recommended working pressure, that's with a pressure gauge ? Looking at the posted pic see too much water disorder coming under rear hull, should be flat when riding at speed. Motor seems a bit high seated on transom, ideal would be for water flow to skim right under the upper deflector plate, that's with motor trimmed to 90 deg and deck weight evenly distributed. Check why is the water flow coming in such a disordered manner ?

Happy Boating

Thanks for your questions. I too thought it was not a clean sheet of water like with a hard hull. i use an electric pump to max pressure 3.4psi.
After I saw the picture I did raise the motor 1 hole but I haven’t taken a pic of it yet. But I do not get any water in the boat under the engine mount.

[Locozodiac]

If flow skims right over uppe plate, water splashes will be produced whether out, side or even over transom as the water flow at speed will be hitting the non edged lower leg portion. If rising the motor one hole seems that the prop will have less water to bite on properly reducing the prop thrust.

Test new motor setting on flat calm water cond as early in the morning as suggested. Test at close tight turns at speed, if prop aerates, motor sits too high. Test the other way if holes permits, that's one hole less from previous posted pic.

Prop will have a better water bed height along thrust, report in which hole height worked better.

Seems that Zodiac model has water flaw issues as the ones reported on the Aerotec models ?

Happy Boating

[jackreno]

Originally Posted by pagick

I went out test my new "used" prop that was suggested would get me 4-5 mph more by two different dealers. But it tests out to be 1 mph lower?
Heres the details-
Zodiac Futura mk2 2013
Evenrude Etec 60hp 2 stroke
Original prop- Solas Amita 3 aluminum 13.25 X 17P top speed 35mph 6100rpm
new prop Evenrude Viper Stainless 13 7/8 X 19P. top speed 34mph 6100 rpm
The new prop did seem to have a touch more punch once the bow drops but only noticeable when swapping back and forth.
Last season the original Solas is delivering 2 mph more but the water was a slight bit rougher on the test day.
Question 1 How could the results be so similar with such a pitch/material difference?
I was exception tho have my rpm drop about 300-400 as well as gain a few mph with the new prop.
Question 2 Looking at the picture should I raise the motor? I did have it up one hole at first but it would ventilate when you trimmed up any. Now that I have some good video it looks low. Also this screen capture was after trimming just below where you hear ventilation.
Thanks for any advice.

I have this install on my Bombard C4 with a 50hp, I can adjust my motor height at any time for shallow water or for more speed, I find my boat preforms better with the motor higher.

https://www.amazon.com/Micro-Jack-Pl...ateway&sr=8-10