Skip to content
BRUNTONSAustralia

Monohull · 13 documented fitments

Propeller upgrade for the Moody 31 — what fits, what changes.

Drawn from 13 documented Moody 31 fitments: the common setup is an Autoprop H5 behind the Volvo Penta 2003. Typical result: 300–400 fewer RPM at cruise and up to 20% fuel saved over fixed pitch.

The fitment card

Documented engine variants & what they wear

Aggregated from 13 real installations — not a size chart, a service record.

EnginePower / max RPMDriveTypical ratioDocumented propellerRotationRecords
Volvo Penta 200328 hp / 3200Shaft2.37:1Autoprop H5Left-hand7
Volvo Penta MD202018 hp / 3600Shaft & saildrive2.48:1Autoprop H20Left-hand2
Lombardini LDW1003M30 hp / 3600Shaft2.6:1Autoprop H5Right-hand1
Volvo Penta MD203028 hp / 3600Shaft2.37:1Sized per boatLeft-hand1
Volvo Penta D1-3029 hp / 3600Shaft2.35:1Autoprop H5Left-hand1
Beta Marine 3030 hp / 3600Shaft2.83:1Varifold 3-bladeRight-hand1

Indicative only — gearboxes and apertures vary between years and repowers, which is why every supplied propeller is verified against your boat first. Data current as of 2026.

Your numbers

What the change feels like on a Moody 31

Indicative curves for this size of boat — drag the cruise line. The independent-test pattern: the same six knots on several hundred fewer RPM, with the fuel flow following.

Moody 31 — speed over RPM, current fixed prop vs Autoprop
024605001k1.5k2k2.5k3kknengine RPMAT 5.2 KN CRUISE24052068 rpm (340)
Fixed 3-bladeAutoprop

Worth knowing

Considerations for the Moody 31

  • Shaft and saildrive variants exist across model years — the APS saildrive series covers the latter; check which yours is before comparing quotes.
  • 6 engine variants are documented for this model — repowers included. Sizing follows your engine and ratio, not the year in the brochure.
  • Tip clearance rules the maximum diameter — roughly 10–15% of prop diameter to the hull. The Builder asks; we verify before supply.

Moody 31 propeller questions

What size propeller does a Moody 31 take?

Documented Moody 31 installations most commonly run an Autoprop H5, matched to the Volvo Penta 2003 on a shaft drive. Exact size depends on your engine, gearbox ratio and aperture — every recommendation is verified by an engineer before supply.

Will an Autoprop fit my saildrive Moody 31?

Yes — saildrive installations are documented for this model, using the APS saildrive variants with the appropriate spline and anodes. Tell us your drive model (e.g. Volvo 130S, Yanmar SD25) and we confirm the fitment.

How much fuel would a Moody 31 save with an Autoprop?

Typical savings over a fixed-pitch propeller are up to 20% at cruise (documented band 15–30%, honestly less if you already run a folding or feathering prop). Put your engine hours and diesel price into the fuel calculator for your own numbers — then the Builder for a verified recommendation.

My Moody 31 has a different engine than shown — does the data still help?

Yes. Repowers are common and the database usually holds several engine variants per model. The Builder starts from your actual engine and gearbox; the model records confirm diameters and clearances that are known to work on this hull.

Get the verified recommendation for your Moody 31

The Builder pre-fills from these 13 documented fitments — confirm your engine and gearbox, and an engineer replies within one business day.