144 documented fitments · 21 hp · 3600 rpm
Propeller for the Yanmar 3YM20.
We've documented 144 propeller installations behind this engine — the ratios, drives and sizes below are what the fleet actually runs.
Rated power
21 hp
Max RPM
3600
Common ratios
2.62:1 · 2.64:1 · 2.21:1 · 2.63:1
Drive split
111 shaft · 33 saildrive
Documented propeller families
The fleet
Boats we've propped with the 3YM20
- Jeanneau SO 349×23
- Beneteau 323×10
- Beneteau Oceanis 31×9
- Jeanneau SO 33i×6
- Jeanneau SO 32i×5
- Beneteau Oceanis 34×4
- Hanse 320×4
- Beneteau 31×3
- Beneteau Oceanis 323×3
- Hanse 342×3
- Catalina 309×2
- Fountaine Pajot 38×2
- Hanse 315×2
- Jeanneau 29.2×2
3YM20 propeller questions
What size propeller suits a Yanmar 3YM20?
It depends on the gearbox ratio behind it (documented installations most often run 2.62:1, 2.64:1, 2.21:1) and the boat it pushes. Power and max RPM set the optimum diameter; the ratio converts engine speed to shaft speed. The Builder runs the numbers and an engineer verifies.
Which propeller family do Yanmar 3YM20 owners fit?
Documented Yanmar 3YM20 installations run Autoprop H5, Varifold 2-blade, Autoprop H20 — the split follows boat type and usage rather than the engine itself.
Does the Yanmar 3YM20 come in shaft and saildrive versions?
Both are documented: 111 shaft and 33 saildrive installations. The propeller differs (hub vs spline fitting) so tell us which yours is.
Running a Yanmar 3YM20?
Two minutes in the Builder — engine pre-filled, gearbox ratio checked against the fleet, verified by an engineer within one business day.