What Is the Yanmar 6LPA Marine Engine?
The Yanmar 6LPA Marine Engine is a compact, high-speed inline six-cylinder marine diesel engine family used in recreational boats, yachts, sport-fishing vessels, repower projects, and other high-performance marine applications.
One of the best-known versions is the Yanmar 6LPA-STP2, rated at 232 kW / 315 mhp at 3800 rpm. Yanmar specifies a 4.164-liter displacement, direct two-stage injection, mechanical controls, turbocharging, and intercooling.
The 6LPA family also appears in different propulsion and installation configurations, including shaft-drive and sterndrive applications. This makes the complete engine designation and serial number especially important when ordering Yanmar 6LPA marine engine spare parts.
Alfa Marine Spare Parts supplies OEM, genuine, aftermarket, and remanufactured Yanmar 6LPA marine engine spare parts for scheduled maintenance, repairs, cooling-system service, fuel-system repairs, major component replacement, rebuilding, and engine overhaul.
Yanmar 6LPA Technical Information
The following specifications are based on Yanmar's published information for the 6LPA-STP2/STC family.
SpecificationYanmar 6LPAEngine TypeFour-stroke marine dieselCylinder ArrangementInlineNumber of Cylinders6Displacement4.164 LBore94 mmStroke100 mmRated Output232 kW / 315 mhpRated Speed3800 rpmCombustionDirect, two-stage injectionAspirationTurbocharged and intercooledEngine ManagementMechanicalCoolingFreshwater + seawater circuitsSeawater PumpRubber-impeller typeStarting SystemElectric, 12 V / 2.5 kWAlternator12 V / 80 ALubricationEnclosed forced lubricationDry Weight Without GearApprox. 408 kg
The exact specification can vary according to the engine version, marine gear, sterndrive, exhaust arrangement, and installation.
Is the Yanmar 6LPA a Six-Cylinder Engine?
Yes.
The Yanmar 6LPA uses a six-cylinder inline configuration.
The published 6LPA-STP2 specification gives:
- 6 cylinders
- 94 mm bore
- 100 mm stroke
- 4.164 L displacement
- Four-stroke operation
- Water cooling
- Turbocharging
- Intercooling
How Much Power Does the Yanmar 6LPA Produce?
For the Yanmar 6LPA-STP2, Yanmar publishes a rated output of:
232 kW / 315 mhp at 3800 rpm.
The exact rating should always be checked against the full engine model.
What Fuel System Does the Yanmar 6LPA Use?
Unlike newer Yanmar engines that use electronic common-rail injection, the 6LPA-STP2 uses a mechanically controlled direct-injection system.
Yanmar describes the combustion system as direct, two-stage injection and the engine management as mechanical.
This distinction is important when sourcing fuel-system components.
Available parts can include:
- Fuel Injectors
- Injector Nozzles
- Fuel Injection Pump Components
- Fuel Supply Pump Components
- Fuel Filters
- Fuel Filter Elements
- Fuel Pipes
- Injector Seals
- Injector Washers
- Fuel-System Gaskets
- Fuel Connections
Yanmar 6LPA Fuel Injector Parts
Fuel injectors have a direct influence on combustion quality.
Available injector-related components can include:
- Complete Fuel Injectors
- Remanufactured Injectors
- Injector Nozzles
- Injector Seals
- Injector Washers
- Injector Hardware
- High-Pressure Fuel Pipes
- Associated Fuel-System Components
Problems in the injection system can contribute to:
- Difficult starting
- Rough running
- Uneven cylinder performance
- Reduced engine power
- Increased exhaust smoke
- Poor acceleration
- Higher fuel consumption
The injector should be identified using the exact engine model, serial number, and existing part number where available.
Yanmar 6LPA Fuel Injection Pump Parts
Because the 6LPA uses mechanical engine management, the fuel-injection pump is an important part of the engine's fuel system.
Available components can include:
- Complete Fuel Injection Pumps
- Fuel Supply Pumps
- Pump Components
- Fuel-Control Components
- Pump Seals
- Pump Gaskets
- Fuel Connections
- Associated Hardware
Fuel-injection components should not be selected based only on the general "6LPA" designation.
Is the Yanmar 6LPA Turbocharged?
Yes.
Yanmar specifies the 6LPA-STP2 as turbocharged and intercooled.
The turbocharger uses exhaust-gas energy to compress the intake air before it enters the engine.
Available turbocharger components can include:
- Complete Turbochargers
- Remanufactured Turbochargers
- Turbocharger Cartridges
- Compressor Components
- Turbine Components
- Turbocharger Shafts
- Bearings
- Seals
- Oil Supply Components
- Oil Drain Components
- Turbocharger Gaskets
- Mounting Hardware
What Does the Yanmar 6LPA Intercooler Do?
Compressed air leaving the turbocharger is hot.
The intercooler removes part of this heat before the air enters the cylinders, helping the engine maintain the intake-air conditions required for efficient combustion.
Available intercooler components can include:
- Complete Intercoolers
- Cooler Cores
- Cooler Housings
- End Covers
- Air Connections
- Intake Pipes
- Hoses
- Clamps
- Gaskets
- O-Rings
- Seals
Yanmar 6LPA Cylinder Head Parts
Available cylinder-head components can include:
- Complete Cylinder Heads
- Intake Valves
- Exhaust Valves
- Valve Guides
- Valve Seats
- Valve Springs
- Rocker Components
- Injector Components
- Cylinder Head Gaskets
- Cylinder Head Seals
- Associated Hardware
The cylinder head operates under significant thermal and mechanical loading, particularly in a high-speed marine engine that regularly operates under sustained load.
Yanmar 6LPA Piston Parts
Available piston-related components can include:
- Pistons
- Piston Rings
- Piston Pins
- Retaining Components
- Associated Hardware
The piston assembly is responsible for receiving combustion pressure and transmitting this force through the connecting rod to the crankshaft.
Piston rings help provide:
- Compression sealing
- Combustion-gas control
- Lubricating-oil control
- Heat transfer toward the cylinder wall
Yanmar 6LPA Connecting Rod Parts
Available components can include:
- Connecting Rods
- Connecting Rod Bearings
- Connecting Rod Bushings
- Connecting Rod Bolts
- Associated Hardware
Yanmar 6LPA Crankshaft and Bearing Parts
Available rotating-assembly components can include:
- Complete Crankshafts
- Main Bearings
- Connecting Rod Bearings
- Thrust Bearings
- Crankshaft Gear Components
- Front Crankshaft Seals
- Rear Crankshaft Seals
- Vibration Damper Components
- Associated Hardware
Yanmar 6LPA Camshaft and Valve Train Parts
Available components can include:
- Camshafts
- Camshaft Bearings
- Timing Components
- Rocker Components
- Intake Valves
- Exhaust Valves
- Valve Guides
- Valve Seats
- Valve Springs
- Associated Hardware
How Is the Yanmar 6LPA Cooled?
The 6LPA uses two connected but separate cooling circuits.
Yanmar specifies freshwater cooling by a centrifugal freshwater pump and seawater cooling by a rubber-impeller seawater pump.
This distinction is important.
The freshwater pump circulates engine coolant through the closed circuit, while the seawater pump brings external raw water through the marine heat-exchange circuit.
Yanmar 6LPA Freshwater Pump Parts
Available freshwater-pump components can include:
- Complete Freshwater Pumps
- Pump Impellers
- Pump Shafts
- Pump Bearings
- Mechanical Seals
- Pump Housings
- Gaskets
- O-Rings
- Associated Hardware
Yanmar 6LPA Seawater Pump Parts
The seawater pump is particularly important in marine service because restricted raw-water flow can quickly reduce the cooling system's ability to reject engine heat.
Yanmar specifically identifies a rubber-impeller seawater pump in its 6LPA technical data.
Available components can include:
- Complete Seawater Pumps
- Rubber Impellers
- Pump Shafts
- Bearings
- Mechanical Seals
- Pump Covers
- Wear Components
- Gaskets
- O-Rings
- Raw-Water Connections
Yanmar 6LPA Heat Exchanger Parts
Available heat-exchanger components can include:
- Complete Heat Exchangers
- Heat Exchanger Cores
- End Covers
- End Caps
- Gaskets
- O-Rings
- Seals
- Raw-Water Connections
- Coolant Connections
- Associated Hardware
Yanmar 6LPA Lubrication System Parts
Yanmar describes the 6LPA-STP2 lubrication system as an enclosed, forced lubricating system.
Available lubrication components can include:
- Engine Oil Pumps
- Oil Filters
- Oil Filter Elements
- Oil Filter Housings
- Oil Coolers
- Oil Pressure Components
- Oil Lines
- Oil Pipes
- Oil Pan Components
- Oil Seals
- Lubrication-System Gaskets
The lubrication system protects critical components such as the:
- Crankshaft
- Main Bearings
- Connecting Rod Bearings
- Camshaft
- Valve Train
- Pistons
- Turbocharger
Yanmar 6LPA Starting and Charging Parts
Yanmar specifies an electric 12 V / 2.5 kW starting system and a 12 V / 80 A alternator for the 6LPA-STP2.
Available components can include:
- Starter Motors
- Alternators
- Starter Solenoids
- Relays
- Wiring Components
- Electrical Connections
- Associated Hardware
Yanmar 6LPA Exhaust Parts
Available exhaust components can include:
- Exhaust Manifold Components
- Exhaust Manifold Gaskets
- Turbocharger Connections
- Exhaust Mixing Elbows
- Exhaust Pipes
- Marine Exhaust Components
- Exhaust Seals
- Mounting Hardware
Yanmar lists a standard exhaust mixing elbow as part of the engine package, with other configurations available depending on installation.
Yanmar 6LPA Gaskets and Seals
Available sealing components can include:
- Cylinder Head Gaskets
- Valve Cover Gaskets
- Intake Gaskets
- Exhaust Gaskets
- Turbocharger Gaskets
- Intercooler Gaskets
- Heat Exchanger Gaskets
- Freshwater Pump Gaskets
- Seawater Pump Gaskets
- Oil Cooler Gaskets
- Injector Seals
- Crankshaft Seals
- O-Rings
- Complete Gasket Sets
- Complete Engine Seal Kits
Yanmar 6LPA Overhaul Parts
Depending on engine condition and overhaul scope, available components can include:
- Pistons
- Piston Rings
- Piston Pins
- Main Bearings
- Connecting Rod Bearings
- Thrust Bearings
- Connecting Rod Components
- Cylinder Head Components
- Intake Valves
- Exhaust Valves
- Fuel Injectors
- Injector Nozzles
- Crankshaft Seals
- Complete Gasket Sets
- Seal Kits
- Freshwater Pumps
- Seawater Pumps
- Oil Pumps
- Turbocharger Components
- Cooling-System Components
Major replacement components can also include:
- Crankshafts
- Camshafts
- Connecting Rods
- Complete Cylinder Heads
- Turbochargers
- Intercoolers
- Heat Exchangers
- Fuel Injection Pumps
What Marine Applications Use the Yanmar 6LPA?
The compact size and high-speed output of the 6LPA make it suitable for marine applications such as:
- Motor Yachts
- Sport-Fishing Boats
- Fast Cruisers
- Recreational Powerboats
- Planing-Hull Vessels
- Light Commercial Craft
- Patrol and Service Craft
- Repower Projects
Yanmar supports 6LPA configurations with shaft-drive transmissions as well as sterndrive arrangements. Its current documentation lists compatible Kanzaki and ZF shaft gears and sterndrive options.
Which Yanmar 6LPA Engine Do I Have?
Before ordering parts, identify the complete engine designation rather than supplying only "Yanmar 6LPA."
For accurate parts identification, provide:
- Complete engine model
- Engine serial number
- Existing part number
- Component description
- Quantity required
- Marine gear or sterndrive information
- Clear photographs of the existing component
- Vessel or application information where relevant
- Delivery country or port
This is especially important for:
- Fuel Injectors
- Fuel Injection Pumps
- Turbochargers
- Seawater Pumps
- Freshwater Pumps
- Heat Exchangers
- Intercoolers
- Starter Motors
- Alternators
- Exhaust Components
- Internal Engine Components
Correct identification helps prevent a component from being selected for the wrong 6LPA configuration.