What prop for 1979 Tayana 37’

[jmurray109]

Re-powering with a rebuilt Yanmar 3GM30F with a Kanzaki KM3P 2.62-1 ratio transmission. The old engine was a a Yanmar 3QM30. The right handed prop is probably the original. The new engine requires a left hand turn prop. Knot looking for anything fancy. No folding/ feathering prop, just a 3 or 4 blade that pushes forward and pulls backwards.

[DougR]

With the engine / reduction ratio that you have, the optimum prop is a 17.5 X 9.5 x 3, or more commonly an 18 x9 x 3. This assumes that the aperture is large enough to fit the prop and still have at least 10% of the diameter tip clearance on the top and the bottom of the prop, and 15% would be even better.

If you don't have room for the 18" prop, the next best is a 17 X 10 x3 or a 16 X11 x3. Anything smaller than the 16" diameter is not recommended as the blade area is getting too small to absorb the available h.p. at the higher RPM.

DougR

[FPNC]

Not sure why you are wanting to turn a left hand wheel.

The Kanzaki KMp3 will be 3.16:1 ratio in left hand rotation.

This transmission is designed for a right hand rotation propeller not a left hand.