Universal M3-20 Marine
Universal Universal M3-20 · M3 family: specifications, its industrial/tractor base engine, cross-referenced parts and where to buy them.
🚜 Base engine confirmed
The Universal M3-20 (18hp 3-cyl) is based on the Kubota D-640 block (Kubota G-6200 mower engine). source
18 hp13.2 kW
719 ccdisplacement
67×68 mmbore × stroke
3-cylcylinders
NAaspiration
Cheaper-part coverage · 6/8
🚜 Base engine ✓🌀 Impeller ✓💧 Raw-water pump🛢️ Oil filter ✓⛽ Fuel filter ✓🌡️ Thermostat ✓➰ Belt⚓ Anode ✓
A ✓ means at least one cheaper channel — aftermarket, the tractor/industrial base engine, or a standard component — exists for this engine in that category.
Parts by section · 42 assemblies
The exploded parts diagrams for the Universal M3-20, grouped by system. Open a figure for its callout part numbers and per-variant quantities.
Body
Fig 1 — Oil PAN GROUPFig 4 — MAIN BEARING CASE GROUPFig 9 — IDUNG APPARATUS GROUPFig 12 — NOZZLE HOLDER GROUPFig 12 — M3-20B Raw Water PumpFig 13 — SPEED CONTROL PLATE GROUPFig 16 — WATER PUMP GROUPFig 17 — M3-20B Throttle AssemblyFig 18 — NAME PLATE GROUPFig 21 — THROTTLE BRACKET GROUPFig 22 — SHERWOOD WATER PUMP 1\1 O. 302
Cooling
Fig 5 — M3-20B Exhaust Manifold and Heat ExchangerFig 11 — M3-20B Cooling SystemFig 20 — HEAT EXCHANGER GROUP
Crankshaft & Pistons
Fig 10 — PISTON. CRANKSHAFT GROUPFig 11 — FLYWHEEL GROUPFig 14 — M3-20B Flywheel and Starter Assembly
Electrical
Fig 16 — M3-20B Alternator AssemblyFig 18 — M3-20B Electrical SystemFig 19 — ALTERNATOR GROUPFig 19 — M3-20B Propulsion Instrument Panels
Engine Block & Head
Fuel
Fig 9 — M3-20B Nozzle Holder and InjectorsFig 10 — M3-20B Governor AssemblyFig 13 — M3-20B Fuel Filter and Oil Drain Hose SystemsFig 14 — GOVERNOR GROUPFig 17 — FUEL FitTER GROUP
Inlet & Exhaust
Lubricating
Miscellaneous
Transmission & Mounting
Fig 3 — GEAR CASE GROUPFig 3 — M3-20B Gear Case AssemblyFig 15 — M3-20B Bell Housing and Transmission
Valve Train
📚 Manuals & Sources
Specs
- Advanced Specifications - Old Model Mfr Westerbeke
Operator's Manual— none yet
Service / Workshop Manual— none yet
Parts Catalog / List
- Parts Manual 200141 Mfr Westerbeke
External links — we host none of these documents.
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- Category
- Marine
- Engine family
- M3
- Cylinders
- 3
- Rated output
- 18 hp (13.2 kW)
- Bore × stroke
- 67 × 68 mm
- Displacement
- 719 cc
- Max rpm
- 3600
- Aspiration
- Naturally aspirated