Water Pump Impeller with Key 19210-ZW9-A31 18-32455 for Honda BF 8 9.9 15 20 HP Outboard
Water Pump Impeller with Key 19210-ZW9-A31 18-32455 for Honda BF 8 9.9 15 20 HP Outboard
Product Overview
Water pump impeller with key for the Honda BF 8, 9.9, 15 and 20 HP outboards, the six blade neoprene impeller and the drive key that turns it. It replaces Honda 19210-ZW9-A31 and 19210-ZW9-A32, it also crosses to Sierra 18-32455, it measures 45.6 mm outside with a 16.2 mm hub, and it ships as one impeller and one key in a 150 mm x 180 mm x 30 mm pack at 22 g.
The impeller sits in the water pump above the lower unit and the key locks it to the drive shaft. Without the key the impeller can spin on the shaft, and a spinning impeller pumps nothing at all even though the blades look perfect.
The body is neoprene with a hardened nylon reinforcement, six blades, 45.6 mm outside and 15 mm high. The nylon takes the load at the hub where the key sits, which is the part that wears out when a pump has been run dry.
The first sign of a tired impeller is a weak tell tale at idle that picks up once the motor revs. Then the engine runs hot at low speed, where the pump does most of its work. Left until the blades let go, the pieces travel up the tube and block the thermostat or the water jacket.
Fitment covers the Honda BFP8D and BFP9.9D models from 2002 and the BF15D and BF20D models from 2003, listed by model below. Check the model and serial number on the bracket before ordering.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Water pump impeller with key |
| Honda Part Number | 19210-ZW9-A31 |
| Also Replaces | 19210-ZW9-A32 |
| Sierra Number | 18-32455 |
| Outer Diameter | 45.6 mm / 1.80 in |
| Hub Shaft Diameter | 16.2 mm / 0.64 in |
| Height | 15 mm / 0.59 in |
| Number Of Blades | 6 |
| Material | Neoprene with hardened nylon reinforcement |
| Drive Key | Included |
| Fits | Honda BF 8, 9.9, 15 and 20 HP outboards |
| Quantity | 1 impeller and 1 key |
| Net Weight | 22 g including packaging |
| Pack Size | 150 mm x 180 mm x 30 mm |
| Pack Size In Inches | 5.91 in x 7.09 in x 1.18 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| Honda | 19210-ZW9-A31 |
| Honda | 19210-ZW9-A32 |
| Sierra | 18-32455 |
Compatible Engines
| Horse Power | Years | Models |
|---|---|---|
| 8 HP | 2002 and newer | BFP8D2, BFP8D3, BFP8D4, BFP8D5, BFP8D6, BFP8DK0, BFP8DK2, BFP8DK3 |
| 9.9 HP | 2002 and newer | BFP9.9D2, BFP9.9D3, BFP9.9D4, BFP9.9D5, BFP9.9D6, BFP9.9DK0, BFP9.9DK2, BFP9.9DK3 |
| 15 HP | 2003 and newer | BF15D3, BF15D4, BF15D5, BF15D6, BFP15D3, BFP15D5 |
| 20 HP | 2003 and newer | BF20D3, BF20D4, BF20D5, BF20D6, BFP20D6 |
Impeller Dimensions
| Measure | Millimetres | Inches |
|---|---|---|
| Outside diameter | 45.6 mm | 1.80 in |
| Hub shaft diameter | 16.2 mm | 0.64 in |
| Height | 15 mm | 0.59 in |
| Blades | 6 | 6 |
| Drive | Key drive, key included | Key drive, key included |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Water pump impeller | Neoprene with hardened nylon, 6 blades, 45.6 mm | 1 |
| Drive key | Locks the impeller to the shaft | 1 |
| Pump housing gasket | Not included, replace it with the impeller | 0 |
| Pump liner and plate | Not included, inspect them while the pump is open | 0 |
Key Features
| Feature | Detail |
|---|---|
| OEM replacement | Built to the Honda 19210-ZW9-A31 size |
| Key included | The drive key comes in the pack with the impeller |
| Cross referenced | Also listed as 19210-ZW9-A32 and Sierra 18-32455 |
| 6 blade neoprene | Hardened nylon reinforcement at the hub |
| 45.6 mm outside | 16.2 mm hub, 15 mm high |
| 8 to 20 HP coverage | Honda BF8, BF9.9, BF15 and BF20 models |
Packing Dimensions
| Measure | Millimetres | Inches |
|---|---|---|
| Pack length | 150 mm | 5.91 in |
| Pack width | 180 mm | 7.09 in |
| Pack height | 30 mm | 1.18 in |
| Weight with packaging | 22 g | 0.78 oz |
Signs The Impeller Needs Replacing
| What You See | What It Means | Action |
|---|---|---|
| Weak tell tale at idle | Impeller taking a set | Fit the new impeller and key |
| Engine hot at low speed only | Pump not moving enough water at idle | Fit the new impeller and key |
| No water at all with a rev | Impeller spinning on the shaft | Fit the new impeller and key |
| Rubber pieces in the tell tale | Blades breaking up | Fit the new impeller and key, flush the passages |
| Overheat after running on muffs | Pump run dry and burned the tips | Fit the new impeller and key |
| Two seasons on the impeller | It is a service part | Fit the new impeller and key as routine |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the model and serial number against the table above |
| 2 | Take the lower unit off and split the water pump housing |
| 3 | Note the order of the liner, plate and gaskets before they come apart |
| 4 | Slide the old impeller off and take out the old key |
| 5 | Check the key slot in the shaft for wear and clean it out |
| 6 | Fit the new key in the shaft, then slide the impeller over it |
| 7 | Bend the blades in the direction of rotation and close the housing |
| 8 | Run the engine on muffs and check the tell tale before use |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Pack, 150 mm x 180 mm x 30 mm |
Before You Buy
- Replaces Honda 19210-ZW9-A31 and 19210-ZW9-A32
- Crosses to Sierra 18-32455
- Fits the Honda BFP8D 8 HP models from 2002
- Fits the Honda BFP9.9D 9.9 HP models from 2002
- Fits the Honda BF15D and BFP15D 15 HP models from 2003
- Fits the Honda BF20D and BFP20D 20 HP models from 2003
- One impeller and one drive key, 22 g with packaging
- 30-Day Easy Returns
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