Yamaha Water Pump Repair Kit 61A-W0078-A3-00

Shop Yamaha Water Pump Repair Kit 61A-W0078-A3-00 for compatible Yamaha outboard engines. This genuine Yamaha water pump repair kit is designed to help restore proper cooling water flow, support steady engine temperature, and protect the outboard from overheating during regular use, long runs, and high-load operation.

Yamaha 61A-W0078-A3-00 is an OEM Yamaha water pump repair kit part number. The safest way to confirm fitment is to match the full part number, Yamaha outboard model, horsepower, and parts diagram before purchasing.

Product Details

• Product name: Yamaha Water Pump Repair Kit
• OEM part number: 61A-W0078-A3-00
• Product type: Yamaha outboard water pump repair kit
• Brand: Yamaha
• System: Outboard cooling system
• Application: Compatible Yamaha outboards where 61A-W0078-A3-00 is specified
• Search variants: Yamaha 61A W0078 A3 00 water pump repair kit, 61A-W0078-A3-00, 61A W0078 A3, Yamaha water pump kit, Yamaha outboard water pump repair kit

What Yamaha 61A-W0078-A3-00 Is Used For

Yamaha 61A-W0078-A3-00 is a genuine Yamaha water pump repair kit used to service the water pump assembly on compatible Yamaha outboards. The water pump helps circulate cooling water through the engine so the outboard can maintain the proper operating temperature.

Use this Yamaha water pump repair kit when your parts diagram or service guidance specifies this OEM part number for the cooling-system service:

• The impeller is worn, stiff, cracked, or damaged
• Cooling water flow is weak
• The telltale stream is inconsistent
• The engine is running hotter than normal
• The outboard triggers an overheat warning
• The lower unit is already being removed for service
• The current water pump has unknown service history
• A Yamaha parts diagram lists 61A-W0078-A3-00
• The existing kit or old service record matches 61A-W0078-A3-00

Because Yamaha water pump parts can vary by model, horsepower, production range, and lower-unit design, part-number confirmation is important before ordering.

Why the Yamaha Water Pump Repair Kit Matters

The water pump is one of the most important parts of a Yamaha outboard cooling system. It moves water through the engine while the motor is running, helping prevent overheating and protecting internal components from heat-related damage.

A worn Yamaha water pump can lead to:

• Weak telltale flow
• Reduced cooling water pressure
• Engine overheating
• Overheat alarms
• Inconsistent engine temperature
• Impeller vane damage
• Worn pump housing or plates
• Poor cooling during long runs
• Higher risk during offshore or high-RPM operation
• Expensive engine repairs if cooling problems are ignored

Replacing worn water pump components during scheduled maintenance helps keep cooling performance predictable and supports long-term Yamaha outboard reliability.

Key Features

• Genuine Yamaha OEM kit – built to Yamaha specifications for compatible outboard cooling system applications
• Complete cooling-system service support – helps refresh key water pump components during maintenance
• Restores water flow – supports proper cooling water circulation through the engine
• Designed for demanding operation – useful for larger Yamaha outboards that run under load or at higher RPM
• Part-number-specific fitment – supports accurate ordering when 61A-W0078-A3-00 is listed for your engine
• Marine-grade construction – designed for heat, friction, water exposure, and harsh marine conditions

Engine and Boat Compatibility

Yamaha Water Pump Repair Kit 61A-W0078-A3-00 is commonly associated with select Yamaha outboard applications, including larger horsepower and V-series engines.

Compatible model references listed for this product include:

• F150 - All Models
• F200 - All Models
• F225 - All Models
• 225 - All Models
• 250 - 1992 and newer
• S150 - All Models
• SX150 - All Models
• S200 - All Models
• SX200 - All Models
• S250 - All Models
• SX250 - All Models
• V150 - All Models
• V250 - All Models
• VX150 - All Models
• VX250 - All Models
• VZ150 - All Models
• VZ200 - 2.6L
• Z150 - All Models
• Z300 - All Models
• P150 - All Models
• P200 - All Models
• C150 - 1997-1999
• PX150 - 1999

Always confirm final fitment by checking your Yamaha model, serial number, parts diagram, and existing water pump part number before ordering.

How to Confirm This Yamaha Water Pump Kit Fits

Confirm fitment before ordering Yamaha Water Pump Repair Kit 61A-W0078-A3-00. Water pump repair kits can vary by Yamaha outboard model, lower-unit design, production range, and cooling system configuration.

Before buying, check:

• Yamaha outboard model
• Engine horsepower
• Serial number or production range
• Existing water pump kit part number
• Yamaha parts diagram
• Service manual recommendations
• Whether 61A-W0078-A3-00 is listed for your engine
• Whether the engine uses A3 or A4 kit variation
• Whether related gaskets, seals, plates, housing parts, or gear lube are also needed

If your parts diagram or old kit lists 61A-W0078-A3-00, this is the correct product page to review.

Yamaha 61A-W0078-A3-00 vs. 61A-W0078-A4-00

Yamaha 61A-W0078-A3-00 and 61A-W0078-A4-00 are similar-looking Yamaha water pump repair kit part numbers, but they should not be treated as interchangeable unless Yamaha fitment information confirms it for your engine.

Use the exact part number listed in your Yamaha parts diagram or service information.

Check carefully for:

• The full part number
• The final suffix, such as A3 or A4
• Engine model compatibility
• Serial-number range
• Lower-unit configuration
• Included kit components
• Supersession notes, if any

For exact-match searches, “Yamaha 61A W0078 A3 00 water pump repair kit” should point to the 61A-W0078-A3-00 product page, not the A4 version.

When to Service a Yamaha Outboard Water Pump

Service a Yamaha outboard water pump during scheduled maintenance or whenever cooling performance decreases. Water pump parts wear over time from heat, friction, water exposure, sand, silt, shallow-water operation, and normal use.

Common times to service the water pump include:

• During annual maintenance
• During 100-hour service
• Before a heavy boating season
• After long storage
• After operating in sand, mud, or shallow water
• When the telltale stream becomes weak
• When engine temperature rises
• When an overheat alarm occurs
• When the service history is unknown
• When the lower unit is already removed

If the engine has overheated, inspect the full cooling system before returning to the water.

Yamaha Water Pump Repair Kit vs. Impeller-Only Replacement

A Yamaha water pump repair kit is usually a more complete service option than replacing the impeller alone. An impeller-only replacement may work when the rest of the pump is in excellent condition, but a repair kit helps refresh more of the assembly.

Use a water pump repair kit when:

• The pump has not been serviced recently
• The impeller shows wear or cracking
• The wear plate needs inspection
• Cooling performance has decreased
• The engine has overheated
• You want a more complete cooling-system service

Use an impeller-only replacement only when the housing, plate, gaskets, and seals are in good condition and Yamaha service guidance allows it.

What to Order With Yamaha 61A-W0078-A3-00

When servicing the Yamaha water pump, review the full lower-unit and cooling-system service needs before starting the job.

Related parts to verify in the diagram include:

• Water pump housing
• Wear plate
• Gaskets
• O-rings
• Seals
• Bolts or hardware
• Lower-unit gear lube
• Drain screw gaskets
• Marine grease
• Thermostat, if cooling issues continue
• Lower-unit service supplies

If the old impeller is missing pieces or badly damaged, inspect cooling passages and related parts before reinstalling the lower unit.

Basic Yamaha Water Pump Service Process

Always follow the Yamaha service manual for your exact outboard model. Water pump service usually requires removing the lower unit, replacing the pump components, and reinstalling the lower unit correctly.

Basic process:

1. Turn off the engine and secure the boat or motor.
2. Disconnect the battery if required by the service procedure.
3. Remove the lower unit according to Yamaha service guidance.
4. Remove the water pump housing.
5. Inspect the old impeller, key, housing, plate, gaskets, and seals.
6. Replace the water pump repair kit components.
7. Lubricate parts where the service manual requires it.
8. Reassemble the water pump housing.
9. Reinstall the lower unit carefully.
10. Refill or check lower-unit gear lube if needed.
11. Run the engine with proper water supply.
12. Confirm strong telltale flow and normal operating temperature.

Do not run the engine without proper water supply. Even brief dry running can damage a new impeller.

Frequently Asked Questions About Yamaha 61A-W0078-A3-00

What is Yamaha 61A-W0078-A3-00?

Yamaha 61A-W0078-A3-00 is a genuine Yamaha water pump repair kit part number used for compatible Yamaha outboard cooling system service.

What does a Yamaha water pump repair kit do?

A Yamaha water pump repair kit replaces worn water pump components to help restore cooling water circulation through the engine and reduce the risk of overheating.

How do I know if 61A-W0078-A3-00 fits my Yamaha outboard?

Confirm fitment by checking your Yamaha outboard model, horsepower, serial number, parts diagram, and existing water pump part number. If your diagram lists 61A-W0078-A3-00, this is the correct product page to review.

Is 61A-W0078-A3-00 the same as 61A-W0078-A4-00?

No, 61A-W0078-A3-00 and 61A-W0078-A4-00 should not be treated as the same part unless Yamaha fitment information confirms the correct replacement for your engine. Always match the exact part number in your parts diagram.

When should I replace my Yamaha water pump repair kit?

Replace or service your Yamaha water pump components during scheduled maintenance or if you notice weak telltale flow, overheating, reduced water pressure, or visible pump wear.

What are signs of a worn Yamaha water pump?

Signs of a worn Yamaha water pump include weak telltale flow, overheating, inconsistent cooling water output, reduced water pressure, cracked impeller vanes, or an overheat alarm.

Can I install Yamaha 61A-W0078-A3-00 myself?

Mechanically experienced boat owners may be able to install this Yamaha water pump repair kit, but professional service is recommended if you are not comfortable removing the lower unit or following Yamaha service procedures.

Should I replace the full water pump kit or only the impeller?

Use the Yamaha service manual and product details to confirm whether your repair requires a complete water pump repair kit or an impeller-only replacement. A full kit is appropriate for complete water pump service. An impeller-only replacement is appropriate only when the remaining water pump components are confirmed to be reusable and compatible with Yamaha service guidance.

• Supersessions
  61A-W0078-A2-00, 61A-W0078-A4-00, 61A-W0078-A4-00, 64L-W0078-00-00, 65L-W0078-A0-00, 65L-W0078-A1-00