cmedsailor
Well-Known Member
Don\'t always blame the propeller....
I would like to share my experience on the following:
I used to blame my 2-blade propeller for not be adequate enough to push the boat satisfactory and was thinking of getting something more powerful (3-blades). I even began a thread in the past about my concerns. I was making tests and could get speeds of 6,3 knots at 2500rpm and 4.5knots on 2000rpm etc, etc on flat, calm water. The boat is fin keel, 6 tonnes, and the engine is 29hp with gearing ratio 2.35:1. The propeller is 2-blade 16X11 with relatively wide blades.
All these concerns disappeared the moment my mechanic found out that there was something wrong with my gear box. Some discs were not good leading to loss of performance and he replaced them.
It felt like changing the engine into something bigger. Suddenly at the same conditions the boat can travel at least 0,5knots faster at any rpm. I can reach almost 7 knots with 2500rpm on a calm day easily.
Just a thing I could never figure out myself.
I would like to share my experience on the following:
I used to blame my 2-blade propeller for not be adequate enough to push the boat satisfactory and was thinking of getting something more powerful (3-blades). I even began a thread in the past about my concerns. I was making tests and could get speeds of 6,3 knots at 2500rpm and 4.5knots on 2000rpm etc, etc on flat, calm water. The boat is fin keel, 6 tonnes, and the engine is 29hp with gearing ratio 2.35:1. The propeller is 2-blade 16X11 with relatively wide blades.
All these concerns disappeared the moment my mechanic found out that there was something wrong with my gear box. Some discs were not good leading to loss of performance and he replaced them.
It felt like changing the engine into something bigger. Suddenly at the same conditions the boat can travel at least 0,5knots faster at any rpm. I can reach almost 7 knots with 2500rpm on a calm day easily.
Just a thing I could never figure out myself.