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Yamaha ME420STI (Hydra Drive) Marine

Yamaha Inboard Yamaha ME420STI (Hydra Drive) · YA-ME family: specifications, its industrial/tractor base engine, cross-referenced parts and where to buy them.

🚜 Base engine likely

The Yamaha ME420STI is a marinized Toyota 1HD-series 4.2 L inline-6 diesel (1HDT / 1HD-FT lineage per rebuild techs). Many internals cross to Toyota 1HD; Yamaha ART pistons/rings and some marinizing parts are proprietary — verify fitment. source

247 hp181.7 kW

4164 ccdisplacement

94×100 mmbore × stroke

6-cylcylinders

from 1991year range (approx)

Turbo + ICaspiration

247 hp @ crankshaft (Batmagasinet 1992 launch data); predecessor to ME421

📋 Full specifications 5 🚜 Industrial / tractor base 🔧 Aftermarket 1

Cheaper-part coverage · 1/8

🚜 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 · 62 assemblies

The exploded parts diagrams for the Yamaha ME420STI (Hydra Drive), grouped by system. Open a figure for its callout part numbers and per-variant quantities.

Other

Fig 1 — CYLINDER HEAD.............................................. 1 FIG. 37 EXHAUST 2 Fig 2 — CYLINDER BLOCK............................................ 3 (TURBO SUPERCHARGER:ME420STI).......... 49 Fig 3 — TIMING GEAR COVER. REAR END PLATE..... 5 FIG. 38 EXHAUST 2 Fig 4 — CRANKSHAFT. PISTON.................................... 7 (TURBO SUPERCHARGER:ME420DTI).......... 51 Fig 5 — CAMSHAFT. VALVE.......................................... 9 FIG. 39 TURBO SUPERCHARGER ASSY..................... 53 Fig 6 — FLYWHEEL HOUSING 1 (ME420STI)............... 12 FIG. 40 THROTTLE CONTROL ATTACHMENT............ 54 Fig 7 — FLYWHEEL HOUSING 2 (ME420DTI)............... 13 FIG. 41 SHIFT ASSIST UNIT (ME420STI) ..................... 55 Fig 8 — MOUNTING 1 (ME420STI) ................................ 14 FIG. 42 SHIFT CONTROL (ME420DTI).......................... 57 Fig 9 — MOUNTING 2 (ME420DTI)................................ 15 FIG. 43 RESERVE TANK. TOOL.................................... 58 Fig 10 — OIL PUMP.......................................................... 17 FIG. 44 GENERATOR..................................................... 59 Fig 11 — OIL FILTER. COOLER....................................... 18 FIG. 45 A.C. GENERATOR ASSY.................................. 60 Fig 12 — OIL COOLER 1 .................................................. 19 FIG. 46 STARTING MOTOR........................................... 61 Fig 13 — OIL COOLER 2 (ME420DTI).............................. 20 FIG. 47 STARTING MOTOR ASSY................................ 62 Fig 14 — LUBRICATION SYSTEM ................................... 21 FIG. 48 ELECTRICAL 1.................................................. 64 Fig 15 — VENTILATION.................................................... 22 FIG. 49 ELECTRICAL 2.................................................. 65 Fig 16 — WATER PUMP (CIRCULATION)....................... 23 FIG. 50 ELECTRICAL 3.................................................. 66 Fig 17 — WATER COOLER (HEAT EXCHANGER) ......... 24 FIG. 51 PULLEYS. BELTS.............................................. 67 Fig 18 — WATER COOLING 1 (OUTLET)........................ 25 FIG. 52 LABELS. CAUTIONS......................................... 68 Fig 19 — WATER COOLING 2 (THERMO UNIT) ............. 26 FIG. 53 TRANSMISSION 1 (HOUSING:ME420DTI)....... 69 Fig 20 — SEA WATER PUMP 1 (ME420STI) ................... 27 FIG. 54 TRANSMISSION 2 Fig 21 — SEA WATER PUMP 2 (ME420DTI)................... 28 (ROTATION & REDUCTION:ME420DTI) ......... 71 Fig 22 — SEA WATER PUMP SUB-ASSY........................ 29 FIG. 55 REPAIR KIT 1 .................................................... 73 Fig 23 — WATER FILTER (SEA WATER) ........................ 30 FIG. 56 REPAIR KIT 2 .................................................... 74 Fig 24 — POWER STEERING PUMP............................... 31 FIG. 57 OPTIONAL PARTS 1 Fig 25 — INTAKE MANIFOLD........................................... 32 (ME420STI:HIGH RAISER)................................ 75 Fig 26 — FUEL PUMP (1996/3 AND BELOW).................. 33 FIG. 58 OPTIONAL PARTS 2 Fig 27 — FUEL PUMP (1996/4 FROM BETWEEN*)......... 34 (ME420DTI:HIGH RAISER) ............................... 76 Fig 28 — FUEL FILTER..................................................... 36 FIG. 59 OPTIONAL PARTS 3......................................... 77 Fig 29 — GLOW PLUG...................................................... 37 FIG. 60 OPTIONAL PARTS 4......................................... 78 Fig 30 — INJECTION NOZZLE......................................... 38 FIG. 61 OPTIONAL PARTS 5......................................... 79 Fig 31 — NOZZLE HOLDER ASSY................................... 39 FIG. 62 OPTIONAL PARTS 6......................................... 80 Fig 32 — ADJUSTING SHIM WIRING CHART (SINGLE).................................................. 81 Fig 33 — INJECTION PUMP............................................. 43 WIRING CHART (TWIN)...................................................... 83 Fig 34 — AIR CLEANER ................................................... 45 WIRING CHART (TWIN: 2 STATION).................................. 84 Fig 35 — AIR COOLER..................................................... 46 NUNERICAL INDEX Fig 36 — EXHAUST 1 ....................................................... 48 Fig 37 — EXHAUST 2 (TURBO SUPERCHARGER:ME420STI)Fig 38 — EXHAUST 2 (TURBO SUPERCHARGER:ME420DTI)Fig 39 — TURBO SUPERCHARGER ASSY Fig 40 — THROTTLE CONTROL ATTACHMENT Fig 41 — SHIFT ASSIST UNIT (ME420STI)Fig 42 — SHIFT CONTROL (ME420DTI)Fig 43 — RESERVE TANK. TOOL Fig 44 — GENERATOR Fig 45 — A.C. GENERATOR ASSY Fig 46 — STARTING MOTOR Fig 47 — STARTING MOTOR ASSY Fig 48 — ELECTRICAL 1 Fig 49 — ELECTRICAL 2 Fig 50 — ELECTRICAL 3 Fig 51 — PULLEYS. BELTS Fig 52 — LABELS. CAUTIONS Fig 53 — TRANSMISSION 1 (HOUSING:ME420DTI)Fig 54 — TRANSMISSION 2 (ROTATION & REDUCTION:ME420DTI)Fig 55 — REPAIR KIT 1 Fig 56 — REPAIR KIT 2 Fig 57 — OPTIONAL PARTS 1 (ME420STI:HIGH RAISER)Fig 58 — OPTIONAL PARTS 2 (ME420DTI:HIGH RAISER)Fig 59 — OPTIONAL PARTS 3 Fig 60 — OPTIONAL PARTS 4 Fig 61 — OPTIONAL PARTS 5 Fig 62 — OPTIONAL PARTS 6

📚 Manuals & Sources

Specs— none yet

Operator's Manual— none yet

Service / Workshop Manual— none yet

Parts Catalog / List— none yet

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Category: Marine
Engine family: YA-ME
Year range (approx): from 1991
Cylinders: 6
Rated output: 247 hp (181.7 kW)
Bore × stroke: 94 × 100 mm
Displacement: 4164 cc
Max rpm: 3800
Aspiration: Turbocharged + intercooled

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