Yanmar 3YM20
2004–present21 HP3-cylinderdiesel
Dieselheat exchanger cooledinboardsaildrive
Modern three-cylinder replacing the 2GM20. Standard in many 28-34ft production boats.
Specifications
| Power | 21 HP @ 3,600 RPM | Cylinders | 3 |
| Displacement | 854 cc (52.1 ci) | Bore x Stroke | 70 x 74 mm |
| Fuel Type | Diesel | Aspiration | Naturally Aspirated |
| Cooling | Heat exchanger | Drive | Inboard, Saildrive |
| Weight | 128 kg (282 lb) | Dimensions (LxWxH) | 694 x 463 x 600 mm |
| Fuel Use | 3.94 L/hr | Oil Capacity | 2.7 L |
| Transmission | KM2P-1 |
Parts for the Yanmar 3YM20
46 catalogued parts. Prices are reference figures; each “Find on Amazon” link opens a search for that part — confirm fitment against your engine's serial before ordering.
Cooling System (9)
Raw Water Pump — Yanmar 2GM/3GMfits: 728270-42002$358.83Buy on
↗
Circulating Water Pump V41 — Yanmar 2YM15/3YM20fits: 20113$212.76Search →
Johnson Impeller Kit F4 MC97$48.39Buy on ↗
Johnson MC97 Pump Impeller 09-810B for Johnson F4 Pumps (6 Blade)$47.38Buy on ↗
Thermostat V18 — Yanmar 2YM/3YMfits: 20111$45.51Buy on ↗
Orbitrade 8-24007 Impeller Kit for Yanmar Engine Cooling Pumps$37.95Buy on ↗- IMPELLER KIT (Includes O-Ring)fits: Yanmar 2GM20-YEU, 2GM20F-YEU, 3GM30-YEU, 3GM30F-YEU, 2YM15, 3YM20, 3YM30(AE)$29.64Buy on ↗
CEF Pump Impeller 09-810B-1 for F4 Pumps (6 Blade)$27.44Buy on ↗- IMPELLER O-RINGfits: Yanmar 2YM15, 3YM20, 3YM30(AE)$5.62Buy on ↗
Fuel System (9)
Fuel Filter — Yanmar 2QM/2YM/3QM/3YMfits: 121370-55601$243.45Buy on ↗- Yanmar Air Filter ( Intake Element )fits: Yanmar 2GM, 2GMF, 3GM , 3GMF, 2GM20 , 2GM20F, 2GM20-YEU, 2GM20F-YEU, 3GM30, 3GM30F, 3GM30-$36.18Buy on ↗
Orbitrade 8-56541 Air Filter Insert for Yanmar 2/3GM & 2/3YM Engines$35.74Buy on ↗
Air Filter V14 — Yanmar 2GM/3GM/2YM/3YMfits: 20601$31.75Search →
Fuel Filter M1 — Yanmar 1GM/2GM/2QM/2YM/3GM/3HM$17.98Search →
Orbitrade 8-55710 Fuel Filter Element for Yanmar Diesel Engines$15.80Buy on ↗- Yanmar Secondary Fuel Filterfits: Yanmar 1GM, 1GM10, 2GM, 2GMF, 3GM, 3GMF, 2GM20, 2GM20F, 2GM20F-YEU, 2GM20-YEU, 3GM30, 3GM3$9.42Buy on ↗
- Yanmar Secondary Fuel Filter O-Ring 1A S-44.0fits: Yanmar Fuel Filter # 104500-55710$2.71Buy on ↗
- Yanmar Nylon Secondary Fuel Filter Housing Bleed Washerfits: Yanmar Fuel Filter # 104500-55710$1.55Search →
Lubrication (5)
Mann W 67/1 Spin On Oil Filter for Kubota Nanni Beta Yanmar$16.90Search →
Yanmar 119305-35170 Oil Filter for TNV & Some TNE Series Engines$15.76Buy on ↗
Oil Filter Kubota Onan — Yanmarfits: 119305-35151$10.58Buy on ↗- Yanmar Oil Filterfits: Yanmar 1GM, 1GM10, 2GM, 2GMF, 3GM, 3GMF, 2GM20, 2GM20F, 2GM20F-YEU, 2GM20-YEU, 3GM30, 3GM3$10.24Buy on ↗
Oil Filter Genuine — Yanmarfits: 119305-35151$9.53Buy on ↗
Belts (6)
- Yanmar Ribbed Belt 37.5"fits: Yanmar 2YM15 (Up to Serial #E05887), 3YM20 (Up to Serial #E11905)$29.98Buy on ↗
- SERPENTINE BELT (VALEO 120 AMP ALT)fits: Yanmar 2YM15 (Serial #E05888 & after) & 3YM20 (Serial #E11906 & after), 2nd Alternator Opt$27.94Buy on ↗
Drive Belt Inboards — Yanmar 3YM15/3YM20/3YM30fits: 119831-42290e$25.40Buy on ↗- Yanmar W/P V-Belt ( M20 )fits: Yanmar 3YM20 (up to Serial #E00303), 3YM30 (up to Serial #E01732)$19.98Search →
- Yanmar V-Belt 37.5"fits: Yanmar 2YM15 (Up to Serial #E05887), 3YM20 (Up to Serial #E11905)$19.48Buy on ↗
- Yanmar W/P V-Belt ( M19 )fits: Yanmar 2GM , 2GMF, 3GM , 3GMF, 2GM20 , 2GM20F, 2GM20-YEU, 2GM20F-YEU, 3GM30, 3GM30F, 3GM30$19.40Buy on ↗
Anodes (2)
Electrical (5)
- STARTERfits: 2YM15, 3YM20, 3YM30(AE) **THIS ITEM IS NON-RETURNABLE**$801.84Buy on ↗
Alternator 12V 55A — Yanmarfits: 129772-77200$256.15Buy on ↗
Starter Motor 3Tn 4Tn V62 — Yanmar 2YM/3JH/3YM/4JHfits: 20307$224.39Search →
Starter Motor — Yanmarfits: 129698-77010$196.88Buy on ↗
Ignition Key 6Ly — Yanmar 2YM/3YM/3JH/4JH/6LPfits: 123482-91291$14.81Buy on ↗
Gaskets & Seals (1)
Exhaust Gasket — Yanmar 2GM/2YM/3GM/3HM/3YMfits: 128370-13201$12.70Buy on ↗
Exhaust (4)
Exhaust Elbow — Yanmar 2GM/2YM/3GM/3HM/3YMfits: 128370-13530$481.62
· $350.00 ↗
Exhaust Mixing Elbow — Yanmar 2YM15/3YM20/3YM30fits: 128890-13530$282.61Buy on ↗
Exhaust Elbow In Stainless Steel Hdi Premium Hdigms — Yanmar 2YM15/2GMF/3YM20/3GM30/3YM30$228.64Search →
Exhaust Bend Elbow In Stainless Steel Hdi Premium Hdiyml — Yanmar 2YM15/3YM30/3YM20$200.06Search →
Service Kits (3)
- Shaft Kit Pump — Yanmar 2GM20/2GM20F/2YM15/3GM30/3GM30F/3YM20fits: 128990-42560$105.85· $164.67 ↗
Orbitrade 8-10030 Service Kit for Yanmar Engines 2YM15/20/30 & 3GM30$104.27Search →
Service Kit Yansrv 20 — Yanmar 3YM20/3YM30$94.21Search →
Engine Mechanical (1)
Mount Marked — Yanmar 2GM/2YM/3GM/3YM/3HM/3JHfits: 100-124772-08341$232.87Search →
Other Parts (1)
Orbitrade 8-4200 Engine Cooling Pump for Yanmar Engines$506.70Search →
Part data aggregated from marine-diesel parts catalogues. As an Amazon Associate, SailPages earns from qualifying purchases.
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