Water Pump Repair Kit – Fits Yamaha 9.9HP & 15HP 4-Stroke (Replaces 63V-W0078-01-00, 63V-W0078-00-00)
Water Pump Repair Kit – Fits Yamaha 9.9HP & 15HP 4-Stroke (Replaces 63V-W0078-01-00, 63V-W0078-00-00) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Water Pump Repair Kit – Fits Yamaha 9.9HP & 15HP 4-Stroke (Repl...
Water Pump Repair Kit – Fits Yamaha 9.9HP & 15HP 4-Stroke (Replaces 63V-W0078-01-00, 63V-W0078-00-00) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Repair Kit – Fits Yamaha 9.9HP & 15HP 4-Stroke Outboard Engines is designed for consistent performance and durability. It provides a reliable solution for maintaining the cooling system on Yamaha 9.9HP and 15HP 4-Stroke outboard engines manufactured from 1996 to the present, including F15, F9.9, and high-thrust T9.9 models.
This kit serves as a direct replacement for OEM part numbers 63V-W0078-01-00 and 63V-W0078-00-00, and is a cross-reference for Sierra parts 18-3433 and 18-3412.
- Enables direct OEM-spec replacement for a perfect fit.
- Available in two primary versions: with or without the water pump housing.
- Engineered for marine environments to ensure longevity.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| Yamaha | 63V-W0078-01-00 | OEM Part |
| Yamaha | 63V-W0078-00-00 | OEM Part |
| Sierra | 18-3412 | Aftermarket equivalent, includes housing. |
| Sierra | 18-3433 | Aftermarket equivalent, without housing. |
| SeaSierra | 18-3412 | Aftermarket equivalent, includes housing. |
| SeaSierra | 18-3433 | Aftermarket equivalent, without housing. |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F15 | 15 | 4-Stroke | 1998–2004 | 63V-W0078-01-00, 63V-W0078-00-00 | |
| Yamaha | F9.9 | 9.9 | 4-Stroke | 1996–2004 | 63V-W0078-01-00, 63V-W0078-00-00 | |
| Yamaha | F15 | 15 | 4-Stroke | 2005–Present | 63V-W0078-01-00, 63V-W0078-00-00 | Also listed as "2006 and Later" |
| Yamaha | F9.9 | 9.9 | 4-Stroke | 2005–Present | 63V-W0078-01-00, 63V-W0078-00-00 | Also listed as "2006 and Later" |
| Yamaha | T9.9 | 9.9 | 4-Stroke | 1996–Present | 63V-W0078-01-00, 63V-W0078-00-00 | High thrust models |
Technical Specs
- Product Type
- Water Pump Impeller Repair Kit
- Installation
- Direct OEM replacement
- Housing Material
- Metal/Aluminum (varies by kit version)
- Housing Color
- Silver
- Weight
- 0.270 kg (0.595 lb)
- Warranty
- 1 Year (varies by distributor)
- Other Technical Attributes
- Two versions available: with or without housing
What’s in the Box
With Housing (18-3412 Version):
- 1 x Impeller (18-3040)
- 1 x Insert Cup (18-3444)
- 1 x Water Pump Housing (18-3356)
- 1 x Impeller Plate (18-3195)
- 1 x Water Seal Damper (18-1833)
- 1 x Impeller Key (NSS)
Without Housing (18-3433 Version):
- 1 x Impeller
- Gaskets and Seals
- Hardware Components
Installation Notes
- Disconnect the battery and remove the engine cover.
- Drain the lower unit gear lube.
- Remove the propeller and the lower unit mounting bolts.
- Carefully slide the lower unit off the driveshaft housing.
- Remove the old water pump housing bolts and lift the housing.
- Slide the old impeller off the driveshaft, noting the keyway position.
- Clean all surfaces and install the new gaskets, plate, cup, and impeller.
- Reassemble the housing and torque bolts to manufacturer specifications.
- Reinstall the lower unit, refill with gear lube, and test the engine's cooling system.
Troubleshooting & FAQ
Which kit do I need—with or without housing?
Choose the kit with housing (18-3412) if your existing housing is corroded, cracked, or warped. If your housing is in good condition, the kit without housing (18-3433) is a cost-effective choice for replacing just the impeller and seals.
What are the signs of a failing water pump impeller?
Common signs include the engine overheating at idle or low speeds, a weak or non-existent "telltale" water stream, or a dry, cracked, or brittle impeller upon inspection. Reduced cooling performance can cause significant engine damage.
How often should the water pump impeller be replaced?
As a general maintenance rule, it is recommended to inspect the impeller annually and replace it every 1 to 2 years, or after every 100-200 hours of use, depending on operating conditions (especially in saltwater or sandy/silty water).
Does this fit all Yamaha 9.9HP engines?
This kit is specifically for 4-Stroke models (F9.9, T9.9) from 1996 to present. It does not fit 2-Stroke models. Always verify your engine's full model name and year before ordering.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials and manufactured in an ISO 9002 facility, with batch-inspections for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
This product is covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window if the product is unused and in its original condition. See our policy page or reach out for instructions.
Safety & Important Info
- Verify images and specifications against your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement part, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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