Sep 22, 2026

Yamaha 15HP Outboard Spare Parts | Complete Engine Parts & Replacement Components

Yamaha 15HP outboard spare parts including crankshaft, piston, CDI, carburetor, impeller, gasket, gear set, drive shaft, lower unit and propeller. Wholesale marine engine replacement parts.

Yamaha 15HP Outboard Spare Parts – Complete Engine Parts Guide

Yamaha 15HP outboard motors are widely used on fishing boats, inflatable boats, small workboats, and recreational vessels. To keep the engine running reliably, regular maintenance and timely replacement of worn components are essential.

We supply a wide range of Yamaha 15HP outboard spare parts, covering almost every major system of the engine, including the powerhead, fuel system, ignition system, cooling system, starter system, lower unit, propeller system, and steering components.

Whether you need parts for routine maintenance, engine repair, or complete rebuilding, we can help you select the correct components according to your Yamaha outboard model and part number.

1. Powerhead & Engine Internal Parts

The powerhead is the main working section of the outboard motor. These components directly affect compression, combustion, power output, and engine durability.

Cylinder Block

The cylinder block forms the main body of the engine and contains the cylinders where combustion takes place.

A damaged or heavily worn cylinder block may cause:

Low compression

Loss of engine power

Excessive oil consumption

Abnormal engine noise

Overheating

For major engine rebuilding, the cylinder block should always be carefully inspected.

Cylinder Head

The cylinder head seals the top of the combustion chamber and works together with the cylinder block, piston, and head gasket.

Common problems include:

Corrosion

Overheating damage

Warping

Water leakage

Combustion gas leakage

A damaged cylinder head can seriously affect compression and engine performance.

Piston

The piston moves inside the cylinder and converts combustion pressure into mechanical power.

A worn or damaged piston may cause:

Low compression

Poor acceleration

Difficult starting

Abnormal knocking

High fuel consumption

Pistons are commonly replaced during engine overhaul.

Piston Ring

Piston rings seal the combustion chamber and help maintain proper compression.

Worn piston rings can result in:

Compression loss

Reduced engine power

Excessive exhaust smoke

Poor fuel efficiency

Piston rings should normally be inspected together with the piston and cylinder.

Connecting Rod

The connecting rod connects the piston to the crankshaft.

It transfers combustion force from the piston to the crankshaft.

Damage to the connecting rod can cause serious internal engine failure, so high-quality replacement parts are especially important.

Crankshaft

The crankshaft converts the reciprocating movement of the pistons into rotational power.

It is one of the most important internal components of a Yamaha 15HP outboard motor.

Possible signs of crankshaft problems include:

Unusual vibration

Knocking noise

Bearing noise

Excessive play

Severe internal engine damage

Crankshaft Bearing

Crankshaft bearings support smooth crankshaft rotation.

Worn bearings may create noise, vibration, or excessive internal clearance.

They should be checked during major engine repair.

Oil Seal

Oil seals prevent lubricant leakage and help prevent water or contaminants from entering critical engine components.

Oil seals are widely used around:

Crankshaft

Drive shaft

Propeller shaft

Gear case

Replacing aged oil seals is an important part of preventive maintenance.

2. Gasket & Seal Parts

Gaskets provide sealing between engine components and prevent leakage of combustion gas, water, fuel, and lubricant.

Common Yamaha 15HP gaskets include:

Cylinder head gasket

Cylinder block gasket

Exhaust gasket

Intake gasket

Carburetor gasket

Water jacket gasket

Gear case gasket

Thermostat gasket

Complete Gasket Set

A complete gasket set is recommended when rebuilding or overhauling the engine.

Replacing old gaskets during disassembly helps prevent future leakage and reduces the need to open the engine again.

3. Fuel System Parts

The fuel system delivers the correct fuel-air mixture to the engine.

A clean and stable fuel supply is essential for easy starting, smooth acceleration, and reliable operation.

Carburetor

The carburetor controls the mixture of fuel and air entering the engine.

Common symptoms of carburetor problems include:

Difficult starting

Unstable idle

Poor acceleration

Engine stalling

Excessive fuel consumption

Carburetor cleaning and repair are common maintenance procedures for Yamaha 15HP engines.

Carburetor Repair Kit

A carburetor repair kit may include:

Gaskets

O-rings

Float needle

Seals

Small internal components

It is commonly used when rebuilding a leaking or blocked carburetor.

Fuel Pump

The fuel pump transfers fuel from the fuel tank to the carburetor or fuel delivery system.

A weak fuel pump can cause:

Fuel starvation

Poor acceleration

High-speed power loss

Difficult starting

Fuel Filter

The fuel filter removes dirt and contaminants before fuel enters the engine.

Regular fuel filter replacement helps protect the carburetor and fuel system.

Fuel Line Hose Assembly

The fuel hose connects the external fuel tank to the outboard motor.

Aging, cracking, or leaking fuel hoses should be replaced immediately.

Fuel hose assemblies normally include:

Fuel hose

Primer bulb

Fuel connectors

Clamps

4. Ignition & Electrical System

The ignition system produces the spark required to ignite the fuel-air mixture.

Electrical components are critical for engine starting and stable operation.

CDI Unit

The CDI controls ignition timing and supplies electrical energy to the ignition coil.

A faulty CDI may cause:

No spark

Intermittent spark

Misfiring

Difficult starting

Engine stopping suddenly

Ignition Coil

The ignition coil converts electrical voltage into the high voltage required by the spark plug.

A damaged ignition coil may cause weak or missing spark.

Charge Coil

The charge coil generates electrical energy used by the ignition system.

Charge coil failure may result in ignition problems or difficulty starting the engine.

Pulser Coil / Trigger Coil

The pulser coil sends crankshaft position and timing signals to the ignition system.

Incorrect signals may cause irregular ignition timing or engine misfiring.

Spark Plug

Spark plugs ignite the fuel-air mixture inside the combustion chamber.

They should be inspected regularly for:

Carbon deposits

Electrode wear

Oil contamination

Incorrect gap

Spark plugs are inexpensive but extremely important maintenance parts.

5. Starter System

Depending on the Yamaha 15HP model, the engine may use manual starting, electric starting, or both.

Recoil Starter Assembly

The recoil starter allows the engine to be started manually by pulling the starter rope.

Main components include:

Starter pulley

Starter spring

Starter rope

Starter pawl

Starter handle

Starter housing

Starter Motor

Electric-start models use a starter motor to rotate the engine during startup.

Common starter motor problems include:

Slow cranking

No cranking

Abnormal noise

Intermittent operation

Starter Relay

The starter relay controls electrical current between the battery and starter motor.

6. Cooling System Parts

Outboard engines depend on water cooling to maintain safe operating temperature.

Cooling system maintenance is especially important because the engine operates directly in marine water.

Water Pump Impeller

The water pump impeller is one of the most important maintenance parts in any outboard motor.

It pumps cooling water through the engine.

A damaged impeller may cause:

Weak cooling water flow

Engine overheating

High cylinder temperature

Serious powerhead damage

The impeller should be inspected and replaced periodically.

Water Pump Repair Kit

A water pump kit may include:

Impeller

Water pump housing

Plate

Gasket

O-ring

Replacing the complete kit is often preferable when multiple pump components are worn.

Thermostat

The thermostat regulates engine operating temperature.

A thermostat stuck closed may cause overheating, while one stuck open may prevent the engine from reaching normal operating temperature.

Water Tube

The water tube transfers cooling water from the lower unit to the powerhead.

Corrosion, blockage, or damage can reduce cooling efficiency.

7. Exhaust System

The exhaust system removes combustion gases from the engine.

Major components may include:

Exhaust manifold

Exhaust cover

Exhaust gasket

Muffler components

Exhaust housing

Carbon buildup, gasket failure, or corrosion may affect exhaust flow and engine performance.

8. Lower Unit / Gear Case Parts

The lower unit transfers engine power through the drive shaft and gears to the propeller.

It operates continuously under heavy load and requires correct lubrication and sealing.

Complete Lower Unit Assembly

A complete lower unit normally includes the gear case and major internal transmission components.

It may be suitable when the existing gear case has severe damage.

Drive Shaft

The drive shaft transfers rotational power from the engine crankshaft to the lower unit gears.

A damaged drive shaft can prevent power transmission to the propeller.

Pinion Gear

The pinion gear receives power from the drive shaft and transfers it to the forward or reverse gear.

Forward Gear

The forward gear drives the propeller shaft when forward gear is selected.

Reverse Gear

The reverse gear allows the propeller to rotate in the opposite direction.

Gear Set

A typical gear set may include:

Pinion gear

Forward gear

Reverse gear

For badly worn transmissions, replacing the matched gear set can provide better gear engagement and durability.

Propeller Shaft

The propeller shaft transfers power from the lower unit gears directly to the propeller.

A bent propeller shaft may cause:

Vibration

Oil seal leakage

Gear case damage

Uneven propeller rotation

Clutch Dog

The clutch dog engages with the forward or reverse gear according to shift position.

Worn clutch dog teeth may cause the engine to jump out of gear.

Shift Cam / Shift Rod

These parts control gear selection between:

Forward

Neutral

Reverse

Difficulty shifting may be related to worn or incorrectly adjusted shift components.

Gear Case Housing

The gear case housing protects the internal gear transmission system.

Damage can be caused by underwater impact, corrosion, or insufficient lubrication.

9. Lower Unit Seals & Bearings

The lower unit contains gear oil and must remain completely sealed against water.

Important components include:

Propeller shaft oil seal

Drive shaft oil seal

O-rings

Bearing housing

Needle bearing

Ball bearing

If gear oil appears milky, water may have entered the gear case.

Oil seals and sealing components should be inspected immediately.

10. Propeller System

The propeller converts engine power into thrust and moves the boat through the water.

Aluminum Propeller

Aluminum propellers are widely used because they are:

Lightweight

Economical

Easy to replace

Suitable for general applications

Stainless Steel Propeller

Stainless steel propellers provide:

Higher strength

Better blade rigidity

Improved durability

Better performance in demanding applications

Propeller selection depends on:

Engine horsepower

Boat size

Boat weight

Gear ratio

Propeller diameter

Propeller pitch

Engine RPM

Operating conditions

Selecting the correct propeller is important for both engine performance and fuel efficiency.

11. Steering & Control Parts

Steering and control components allow the operator to control engine direction, throttle, and gear selection.

Steering Handle / Tiller Handle

The tiller handle is commonly used on smaller Yamaha outboards.

It may contain:

Throttle grip

Stop switch

Steering handle

Control cable

Internal throttle components

Steering Bracket

The steering bracket supports engine steering movement and connects the outboard to the mounting structure.

Swivel Bracket

The swivel bracket allows the outboard motor to rotate for steering.

Clamp Bracket

The clamp bracket secures the engine to the boat transom.

Throttle Cable

The throttle cable controls engine speed.

Shift Cable

On remote-control models, the shift cable controls forward, neutral, and reverse gear selection.

12. Engine Mounting Parts

Engine mounting components absorb vibration and securely connect the engine assembly.

Common parts include:

Upper engine mount

Lower engine mount

Mounting bolts

Rubber dampers

Brackets

Worn rubber mounts can create excessive vibration.

13. Anode

The sacrificial anode protects metal components from galvanic corrosion.

This is especially important when the engine is used in saltwater.

The anode should be inspected regularly and replaced when heavily consumed.

Never paint over the surface of the anode.

14. Cowling & External Parts

External parts protect the engine and provide structural support.

Common components include:

Top cowling

Bottom cowling

Cowling seal

Cowling latch

Engine cover

Air intake components

Rubber seals

Damaged cowling seals may allow excessive water or moisture to enter the engine compartment.

Main Yamaha 15HP Spare Parts Categories

For easier sourcing, Yamaha 15HP outboard spare parts can generally be divided into the following categories:

Powerhead parts

Piston and crankshaft parts

Gaskets and seals

Fuel system parts

Carburetor parts

Ignition and electrical parts

Starter parts

Cooling system parts

Water pump parts

Exhaust parts

Lower unit parts

Gear set components

Drive shaft and propeller shaft

Bearings and oil seals

Propellers

Steering components

Engine mounting parts

Cowling and external parts

Maintenance kits

Which Yamaha 15HP Parts Are Replaced Most Often?

For normal maintenance and repair, several components have a higher replacement frequency.

Regular Maintenance Parts

These normally include:

Water pump impeller

Water pump repair kit

Spark plug

Fuel filter

Fuel hose

Gaskets

Oil seals

Thermostat

Anode

These components should be inspected periodically to reduce the risk of major engine damage.

Common Repair Parts

Depending on engine condition, repair shops may frequently require:

Carburetor repair kit

Fuel pump

Ignition coil

Recoil starter parts

Drive shaft

Propeller shaft

Gear set

Lower unit seals and bearings

Engine Rebuilding Parts

For engines requiring major overhaul, commonly needed parts include:

Piston

Piston rings

Connecting rod

Crankshaft

Bearings

Cylinder components

Complete gasket set

Oil seals

Choosing the Correct Yamaha 15HP Spare Parts

Not every Yamaha 15HP outboard uses exactly the same parts.

Parts may vary depending on:

2-stroke or 4-stroke engine

Engine model

Production year

Short shaft or long shaft

Manual start or electric start

Tiller control or remote control

Regional engine specification

Before ordering parts, we recommend checking:

1. Engine model number

Check the identification label on the outboard motor.

2. Original part number

Providing the OEM part number is one of the easiest ways to identify the correct component.

3. Product photo

Photos of the old part can help confirm shape and configuration.

4. Engine serial number

For some applications, the serial number can help identify production differences.

Yamaha 15HP Parts for Repair Shops, Dealers & Distributors

We supply Yamaha 15HP outboard spare parts for:

Outboard motor repair shops

Marine spare parts stores

Boat repair companies

Marine equipment distributors

Outboard parts wholesalers

Fishing boat operators

Importers and trading companies

We can support both individual replacement parts and mixed wholesale orders.

Our product range covers common maintenance parts as well as engine rebuilding and lower-unit repair components.

Why Quality Matters for Yamaha 15HP Outboard Parts

Outboard engines operate under demanding conditions including:

Continuous vibration

High engine RPM

Saltwater exposure

Humidity

Heavy mechanical load

High operating temperature

Low-quality components may cause premature wear or repeated repairs.

For critical components such as crankshafts, pistons, gears, bearings, ignition parts, water pump components, and oil seals, correct dimensions and reliable material quality are especially important.

Yamaha 15HP Outboard Spare Parts Supplier

Looking for Yamaha 15HP outboard spare parts?

We provide a wide selection of replacement parts covering engine maintenance, repair, lower-unit rebuilding, ignition systems, fuel systems, cooling systems, and propeller applications.

Available products include:

For accurate quotation and part identification, please send us your:

Yamaha engine model + horsepower + OEM part number + quantity.

We support wholesale inquiries and international supply of outboard motor spare parts