Yamaha 6 8 HP Outboard Water Pump Impeller Kit 6G1-W0078-A1 Sierra 18-3460
Yamaha 6 8 HP Outboard Water Pump Impeller Kit 6G1-W0078-A1 Sierra 18-3460
Product Overview
Water pump impeller repair kit, a complete pump service part for the Yamaha 6 HP and 8 HP two-strokes and the Mariner 6 and 8 HP built on the same powerhead. It replaces the Yamaha kit numbers 6G1-W0078-00, 6G1-W0078-01 and 6G1-W0078-A1, the short kit 6N0-W0078-A0 and Sierra 18-3460.
The kit is built around the impeller 6G1-44352-00 and contains the cartridge insert, the outer plate and the two wear plates that the impeller runs against, plus the gasket, the water seal and the 4 housing bolts. That is the whole pump apart from the housing itself, which is why it is the kit to buy on an engine that has sat through a winter.
These small Yamahas are the mainstay of tenders, inflatables and small lake boats, and the pump is the part that suffers first. An impeller that has taken a set still turns and still looks intact, but it delivers a fraction of the water at idle, which is where a 6 HP engine spends most of its life.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Water pump impeller service kit |
| Engine Type | Yamaha and Mariner two-stroke outboards |
| Horsepower | 6 HP, 8 HP |
| Impeller Part Number | 6G1-44352-00 |
| Components | 8 items, see list below |
| Net Weight | 46 g |
| Country of Origin | Taiwan |
OEM Cross Reference
| Reference | Part Numbers |
|---|---|
| Yamaha pump kit | 6G1-W0078-00, 6G1-W0078-01 |
| Yamaha pump kit | 6G1-W0078-A1 |
| Yamaha short kit | 6N0-W0078-A0 |
| Sierra | 18-3460 |
| Yamaha impeller | 6G1-44352-00 |
| Sierra impeller | 47-11590M |
| Yamaha cartridge insert | 6G1-44322-00 |
| Yamaha cartridge outer plate | 6G1-44323-00 |
| Yamaha wear plate | 6G1-44328-00 |
Assembly Components
| Component | Qty | Part Number |
|---|---|---|
| Impeller | 1 | 6G1-44352-00 |
| Cartridge insert | 1 | 6G1-44322-00 |
| Cartridge outer plate | 1 | 6G1-44323-00 |
| Wear plate | 2 | 6G1-44328-00 |
| Water pump gasket | 1 | Not published |
| Water seal | 1 | Not published |
| Housing bolt | 4 | Not published |
Compatible Engines
| Brand | Horsepower | Years |
|---|---|---|
| Yamaha | 6 HP | 1988-2000 |
| Yamaha | 8 HP | 1984 and later |
| Mariner | 6 HP | 1984-1986 |
| Mariner | 8 HP | 1984-1986, 2002-2006 on the later 8M suffix models |
What's Included
| Component | Qty |
|---|---|
| Water pump gasket | 1 |
| Cartridge insert | 1 |
| Cartridge outer plate | 1 |
| Impeller | 1 |
| Water seal | 1 |
| Wear plate | 2 |
| Hexagon housing bolt | 4 |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Check the engine model suffix against the years above, the 6 and 8 HP pumps changed across the model runs
- Compare the old impeller with 6G1-44352-00 before fitting, the 4 and 5 HP engines use a different pump
- Inspect the plastic housing for scoring, a grooved housing will wear the new impeller in a season
- Lubricate the impeller with glycerine and turn the shaft clockwise as the pump goes back together
- Torque the 4 housing bolts evenly, an uneven housing will not hold prime at idle
- Run the engine on muffs and check the telltale before leaving the ramp
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Boat Owners' Review
Before You Buy
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