Yanmar 3YM30 Cruiser Inboard Marine Diesel Engine

Description

Tired of excessive vibration and underpowered headwind motoring in your coastal cruising yacht? The Yanmar 3YM30 Cruiser Engine cures underperformance with a 1.115L 3-Cylinder displacement block generating 29.1 BHP at 3,600 RPM. Swirl chamber indirect injection requires clean diesel fuel, and the closed freshwater heat exchanger requires anti-freeze coolant maintenance to safeguard internal cylinder water jackets.

A parent bore high-strength cast iron block supports heavy combustion pressures across three cylinders. The single-piece cast iron cylinder head contains swirl combustion chambers actuated by mechanical pushrods. Electrical hardware includes an isolated 12V earth circuit featuring a 1.4 kW starter motor and a high-output 12V 125A alternator. Dimensions span 28.2in long, 18.2in wide, and 23.6in high, weighing 293 lbs with reduction gear. Oil pan volume holds 0.74 US gal.

Key Features of Yanmar 3YM30

Displacement yacht owners buy Yanmar 3YM30 cruiser marine diesel engines to repower 30ft to 38ft sailboats and canal boats with dependable shaft propulsion. Marine yards choose this package for commercial workboat diesel engine repower installations in coastal pilot tenders.

• Mechanical indirect injection with in-line Bosch pumps produces smooth combustion without electrical dependency
• Atmospheric induction with tuned intake resonators reduces air induction rumble inside boat cabins
• Tubular freshwater heat exchangers isolate raw ocean water from internal cast iron cooling galleries
• High-output 12V 125A alternators recharge large marine house battery banks during short harbor transits
• Torsional vibration dampers isolate crankshaft power pulses from marine transmissions and shafting
• Direct mounting flanges mate with Yanmar KM2P-1 mechanical gearboxes or SD25 saildrive units
• Front-facing maintenance checkpoints streamline routine impeller checks and oil filter changes

Bench Dynamometer Load Test Output

Dynamometer test records confirm 29.1 BHP peak output at 3,600 RPM and 27.3 BHP continuous output at 3,489 RPM. Closed freshwater heat exchangers hold core coolant temperature steady at 178°F under continuous thermal load. Engine oil pressure maintains 45 PSI across operational engine speeds. Shaftline installation permits up to 15° static inclination angles. Crankshaft journal runout remains below 0.0004in TIR to protect bearings against deflection fatigue. Exhaust temperatures stay below 1,060°F during full power dyno testing runs.

Field Operation Maintenance Service Rules

Mechanical control linkages provide positive detent action with under 2 lbs of lever resistance. Do not install this 29.1 BHP auxiliary engine in heavy commercial displacement tugs, fast planing skiffs, or vessels requiring high-speed towing capabilities. Operators must monitor freshwater coolant glycol levels and inspect the heat exchanger zinc anode at regular intervals.

• Drain engine oil and change spin-on oil filter cartridges every 150 operating hours
• Inspect raw water pump impellers and check heat exchanger zinc anodes every 150 hours
• Replace the primary 10-micron fuel water separator filter cartridge every 250 engine hours

Factory Warranty Shipment Parts Manifest

Yanmar Marine provides a 2-Year limited warranty backed by 3-Year major component structural coverage. The shipment crate contains the 3YM30 diesel engine core, KM2P-1 mechanical gearbox, high-output 12V 125A alternator, 1.4 kW starter motor, flexible engine mounts, B20 instrument panel, wiring harness, and factory technical manuals.