Honda Marine 4-Stroke Outboard Engine Parts

(134 products)

This page is for Honda Marine 4‑Stroke outboard engines. It helps you find compatible parts and service information, including maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse our main Honda collection for a wider selection. Scroll to the bottom of the page to start browsing parts for this engine, and remember that on the collection page you can use the Filter & Sort controls to narrow results by horsepower, year range, and part category.

Browse All Honda Parts

How to Identify Your Honda 4‑Stroke Model

Locate the nameplate: On most Honda outboards, the model/serial plate is on the transom bracket (typically starboard side) or the swivel bracket. Record the full model code and serial number.
Read the model code: Examples include BF2.3, BF5, BF8/9.9, BF15/20, BF25/30, BF40/50, BF60, BF75/90/100, BF115/135/150, BF200/225/250, and BF350. Suffix letters and numbers indicate shaft length (e.g., S/L/X), control type (tiller vs. remote), and series revisions.
Platform clues: Portables (2.3–20 hp) are single- or twin‑cylinder; mid‑range (25–100 hp) are typically inline‑3/inline‑4; high power (115–250 hp) include inline‑4 and V6; BF350 is a V8. iST electronic controls are available on many 115–350 hp models.
Confirm year/fitment: Use the serial number against a parts reference to confirm the exact series and compatibility. Many components changed across series updates even at the same horsepower.

Platform Overview

Portable Series (2.3–20 hp)

Feature	Description
Configuration	Air‑cooled (2.3 hp) and water‑cooled single/twin‑cylinder 4‑stroke designs
Common Models	BF2.3, BF5, BF8/9.9, BF15/20
Advantages	Lightweight, easy starting, low fuel consumption
Notes	Impellers, plugs, and anodes are routine service items; verify shaft length and tiller/remote control when selecting parts

Mid‑Range Series (25–100 hp)

Feature	Description
Configuration	Inline‑3 and inline‑4 4‑stroke EFI platforms
Common Models	BF25/30, BF40/50, BF60, BF75/90/100
Advantages	Good mid‑range torque, smooth operation, strong fuel economy
Notes	Propellers, water pump kits, and anodes vary by gearcase; confirm model suffix and serial for exact fit

High Power Series (115–250 hp)

Feature	Description
Configuration	Inline‑4 (115/140/150) and V6 (200/225/250) EFI 4‑stroke platforms; many support iST electronic controls
Common Models	BF115/140/150; BF200/225/250
Advantages	Strong performance, refined NVH, broad propeller options
Notes	Rigging parts (controls, harnesses) differ between mechanical and iST; verify gearcase ratio and prop hub type before ordering

BF350 V8

Feature	Description
Configuration	V8 4‑stroke EFI with advanced control integration
Common Models	BF350
Advantages	High output with refined fuel economy for its class
Notes	Uses model‑specific rigging; always confirm control system components and propeller hub kits

Routine Maintenance & Service Parts

Intervals below are general guidelines for Honda 4‑Stroke outboards. Always follow the official service manual for your exact model and operating conditions.

Item	Interval*	Remarks	Parts Link
Engine oil + filter	First 20 hours, then every 100 hours or annually	Use marine‑grade FC‑W oil; replace crush washer where applicable	Oil Filters
Gear oil (lower unit)	Every 100 hours or annually	Inspect for water intrusion (milky oil) and metal debris; replace seals if leakage is found	Honda Lower Unit Seal Kits
Spark plugs	Inspect every 100 hours; replace 200–300 hours or as needed	Gap and plug type vary by model; replace sooner for extended trolling or fouling	Spark plug
Fuel filter / water separator	Every 100 hours or each season	Drain or replace more frequently with ethanol fuel or contamination	Fuel Filters
Water pump impeller / kit	Every 2–3 seasons or 200–300 hours	Replace sooner if weak tell‑tale, overheating, or sand/silt operation	Honda Water Pump Repair Kits
Anodes (sacrificial)	Inspect monthly; replace when ~50% consumed	Use the correct alloy for fresh, brackish, or saltwater	Anodes

Frequently Used Parts Categories

Routine Service – Service & Maintenance Kits
Cooling System – Honda Water Pump Repair Kits
Fuel System – Fuel Filters
Ignition / Electrical – Electrical Items
Propulsion – Propellers
Gearcase & Seals – Honda Lower Unit Seal Kits
Corrosion Protection – Anodes

Common Symptoms & Quick Checks

Symptom	Check First	Related Parts
Weak tell‑tale or overheat alarm	Inspect intake screens for blockage, verify impeller condition, test thermostat	Water pump kit, thermostat, intake screen, anodes
Hard starting or rough idle	Check fuel quality, primer bulb, and filters; inspect spark plugs and plug caps	Fuel filter, spark plugs, primer bulb, ignition leads
Poor acceleration or power loss	Look for damaged or fouled propeller, fuel restriction, dirty plugs; confirm throttle opening	Propeller, fuel filter, spark plugs
Gearcase noise or metal in gear oil	Check oil level/condition; inspect for fishing line on prop shaft damaging seals	Lower unit seal kit, bearings, prop shaft hardware

FAQs

Are parts interchangeable across different years or platforms?

Some consumables (plugs, anodes, filters) may be shared within a series, but changes between series revisions and platforms are common. Always verify compatibility by full model code and serial number.

When should I replace the water pump impeller?

As a preventive measure every 2–3 seasons or 200–300 hours. Replace sooner if the tell‑tale weakens, you operate in sand or silt, or any overheat event occurs.

How often should I change the gear oil?

Every 100 hours or annually. Inspect for milky appearance (water intrusion) or metal debris; if present, address seals or internal wear before further operation.

What information do you need to confirm part fit?

Please provide the full model code, serial number, horsepower, shaft length, and control type (tiller or remote). Photos of the nameplate and the existing part help ensure an exact match.

Ready to find the right components? Browse the main Honda collection by horsepower, year, and model.

Shop Honda Outboard Parts

If you’re unsure about your model, send us a photo of the nameplate and the part you need and we’ll help verify compatibility.