Water Pump Impeller with Key 389642 18-3043 for Johnson Evinrude V4 V6 85 235 HP Outboard
Water Pump Impeller with Key 389642 18-3043 for Johnson Evinrude V4 V6 85 235 HP Outboard
Product Overview
Water pump impeller with key for the Johnson and Evinrude V4 and V6 outboards from 85 to 235 HP, the six blade impeller and the drive key that turns it. It replaces Johnson Evinrude 389642 and 385528, it also crosses to Sierra 18-3043, it measures 90.2 mm outside with a 22.3 mm shaft bore, and it ships as one impeller and one key in a 150 mm x 180 mm x 30 mm pack at 177 g.
This is the V4 and V6 impeller: 90.2 mm across, 32.2 mm high, six blades, neoprene body with a brass hub. The size is what sets it apart from the smaller crossflow impellers, so measure the old one if there is any doubt.
The impeller turns with the drive shaft and the key locks it in place. The blades bend against the pump liner and push water up the tube to the powerhead. A key that has worn or dropped out lets the impeller spin on the shaft, and then the pump moves nothing at all.
A tired impeller shows as a weak tell tale at idle that picks up once the motor revs, then an engine that 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 Johnson and Evinrude V4 and V6 85, 115, 135, 140, 150, 175, 200 and 235 HP outboards from 1973 to 1978, with the years for each rating set out 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 |
| Johnson Evinrude Part Number | 389642 |
| Also Replaces | 385528, 777212, 777823 |
| Also Replaces | 0389642, 0385528, 0777212, 0777823 |
| Sierra Number | 18-3043 |
| Outer Diameter | 90.2 mm / 3.56 in |
| Height | 32.2 mm / 1.27 in |
| Shaft Diameter | 22.3 mm / 0.88 in |
| Number Of Blades | 6 |
| Material | Neoprene with brass hub |
| Drive Key | Included |
| Fits | Johnson and Evinrude V4 and V6, 85 to 235 HP |
| Quantity | 1 impeller and 1 key |
| Net Weight | 177 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 |
|---|---|
| Johnson / Evinrude | 389642, 385528, 777212, 777823 |
| Johnson / Evinrude | 0389642, 0385528, 0777212, 0777823 |
| Sierra | 18-3043 |
Compatible Engines
| Brand | Horse Power | Years |
|---|---|---|
| Johnson / Evinrude | 85 HP | 1973 - 1978 |
| Johnson / Evinrude | 115 HP | 1973 - 1978 |
| Johnson / Evinrude | 135 HP | 1973 - 1976 |
| Johnson / Evinrude | 140 HP | 1977 - 1978 |
| Johnson / Evinrude | 150 HP | 1976 - 1978 |
| Johnson / Evinrude | 175 HP | 1976 - 1978 |
| Johnson / Evinrude | 200 HP | 1976 - 1978 |
| Johnson / Evinrude | 235 HP | 1978 |
Impeller Dimensions
| Measure | Millimetres | Inches |
|---|---|---|
| Outside diameter | 90.2 mm | 3.56 in |
| Height | 32.2 mm | 1.27 in |
| Shaft diameter | 22.3 mm | 0.88 in |
| Blades | 6 | 6 |
| Drive | Key drive, key included | Key drive, key included |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Water pump impeller | Neoprene, brass hub, 6 blades, 90.2 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 Johnson Evinrude 389642 size |
| Key included | The drive key comes in the pack with the impeller |
| Cross referenced | Also listed as 385528 and Sierra 18-3043 |
| Brass hub | Holds the key slot true and resists corrosion |
| V4 and V6 impeller | 90.2 mm outside diameter, 32.2 mm high |
| 85 to 235 HP coverage | Johnson and Evinrude V4 and V6, 1973 to 1978 |
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 | 177 g | 6.24 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, horsepower and year 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 and the brass hub for wear |
| 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 Johnson Evinrude 389642 and 385528
- Also replaces 777212, 777823, 0389642, 0385528, 0777212 and 0777823
- Crosses to Sierra 18-3043
- Fits the Johnson and Evinrude V4 and V6 from 85 to 235 HP
- 85, 115, 135, 140, 150, 175, 200 and 235 HP, 1973 to 1978
- 6 blades, 90.2 mm outside diameter, 22.3 mm shaft bore
- One impeller and one drive key, 177 g with packaging
- 30-Day Easy Returns
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Before You Buy
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