I have an old 2-stroke yamaha (5C) outboard
from -87 on my 25' sailboat, which still runs fine. It has a 7 1/2 x 8 propeller
, which is too a high pitch
for a sailboat. In reverse, the traction is horrible and in forward the engine
runs very heavy, with a blurry sound. This propeller
looks like the shine one in the first picture.
Now, I have found a propeller with lower pitch
(7 1/4 6 1/2), looks like the one in the second picture. From what I have understood, props for sailboat outboards generally have 1. lower pitch, 2. larger surface area, 3. often four blades.
The yamaha props with <7" pitch seem to all look like the second pic below. Smaller surface area. 1/4 inch smaller diameter.
Does anyone have an idea whether such a prop would actually provide more thrust?
Bonus question: found a manual online that says both type "-B" and "-BA" props will fit the 5C. Yet -B has pin drive, while -BA has splines and no pin socket. That can't work, can it?