Water Pump Impeller 777817 386084 0386084 18-3050 for Johnson Evinrude 8 9.9 10 15 HP Outboard 6 Blade 38.10 mm Round Hub — Australia Local Warehouse
Water Pump Impeller 777817 386084 0386084 18-3050 for Johnson Evinrude 8 9.9 10 15 HP Outboard 6 Blade 38.10 mm Round Hub — Australia Local Warehouse
Product Overview
Water pump impeller for Johnson and Evinrude outboards from 8 HP to 15 HP, a cooling system part with 6 blades, 38.10 mm outer diameter, 12.75 mm hub and 17.86 mm height. It replaces OMC 777817 and 386084 and crosses to Sierra 18-3050. Shipped from our Australia local warehouse.
This is the small lower unit impeller on the 9.9 and 15 HP two stroke family, the one that sits directly under the water pump plate on the driveshaft. It is a plain round hub with no key and no spline, driven by the shaft fit alone, so a polished shaft matters as much as a new impeller.
The same impeller is sold as 777817 by OMC and as 18-3050 by Sierra, and it is common to both Johnson and Evinrude badges because the gearcases are identical. Change it with the gear oil and the job does not have to be repeated in the same season.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Outboard water pump impeller |
| Blades | 6 |
| Outer Diameter | 38.10 mm (1-1/2 in) |
| Hub Diameter | 12.75 mm |
| Height | 17.86 mm |
| Material | Neoprene |
| Net Weight | 19 g |
| Country of Origin | Taiwan |
Dimension Notes
| Measurement | Figure |
|---|---|
| Outer diameter, nominal | 38.10 mm |
| Hub diameter, nominal | 12.75 mm |
| Height, nominal | 17.86 mm |
| Figures quoted on the eBay listing | 37.65 mm outer, 12.74 mm hub, 16.87 mm high, 18 g |
| Drive | Round hub, no key, no spline |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| OMC / Johnson / Evinrude | 386084, 0386084 |
| OMC / Johnson / Evinrude | 777817, 0777817 |
| Sierra | 18-3050 |
| Mallory | 9-45201 |
| CEF | 500355 |
| Cross reference | 47-00587 |
Compatible Engines
| Brand | Horsepower | Years |
|---|---|---|
| Johnson / Evinrude | 8 HP | 1996 to 1998, 2003 |
| Johnson / Evinrude | 9.9 HP | 1975 to 1977, 1979, 1982, 1984 to 1999 |
| Johnson / Evinrude | 10 HP | 1997, 2000 to 2001, 2006 to 2007 |
| Johnson / Evinrude | 15 HP | 1975 to 1977, 1984 to 1992, 1995, 1997, 1999, 2001, 2004 |
What's Included
| Component | Reference | Qty |
|---|---|---|
| Neoprene impeller, 6 blade round hub | 777817 pattern, 38.10 mm by 17.86 mm | 1 |
Driveshaft Fit and the Housing Liner
| What You Find | What It Means | What To Do |
|---|---|---|
| Driveshaft polished and dry | Hub cannot grip, impeller slips | Clean and grease the shaft, check the hub bore |
| Scored lines on the driveshaft | Old impeller ran dry and spun | Shaft may need replacing with the impeller |
| Housing liner grooved | New impeller wears out in weeks | Renew the liner and the plate with the impeller |
| Plate pitted under the blades | Flow falls even with a new impeller | Fit a new plate at the same time |
| Hub bore opened up | Impeller rocking on the shaft | Wrong part or a worn shaft, check both |
| Old impeller cut off the shaft | Blades and hub ring left in the pump | Remove every piece before refitting |
Salt Water and Small Outboards in Australia
| How the Motor Is Used | Effect on the Impeller | What To Do |
|---|---|---|
| Tender or tinny, salt water | Salt dries on the blades between trips | Flush on muffs after every trip |
| Sand and mud ramps | Grit eats the liner and the plate | Check the liner each season |
| Tropical north, warm water | Blades harden and crack with heat | Renew every season |
| Motor tilted up between trips | Pump drains, runs dry on start | Lower fully and prime before starting |
| Long idle at trolling speed | Blades ride on one side of the cam | Run up to cruise regularly |
| Boat ashore in the dry season | Blades take a set in the housing | Renew before the season starts |
Overheat and the Telltale
| What You See | What It Points To | What To Check |
|---|---|---|
| No telltale at idle | Impeller worn or the intake blocked | Clean the intake, then strip the pump |
| Telltale strong at idle, hot at speed | Impeller slipping on a dry shaft | Shaft and hub fit, plus the liner |
| Rubber crumbs from the telltale | Impeller breaking up | Find every blade before reassembly |
| Overheat after a gear oil change | Impeller refitted dry or backwards | Blades must fold in the running direction |
| Hot only after a long run | Plate and liner worn | Renew the plate with the impeller |
| Steady telltale, normal temperature | Pump is sound | Keep the interval, change at the seasons |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the number on the old impeller, 777817 and 386084 are the same part |
| 2 | Check the horsepower and year against the table, the 9.9 and 15 HP share this impeller |
| 3 | Check the driveshaft for scoring, a polished shaft lets a new impeller slip |
| 4 | Check the pump housing liner and the plate for grooves before refitting |
| 5 | Grease the shaft and the bore, then fold the blades in the running direction |
| 6 | Slide the impeller down squarely, do not drive it with a hammer |
| 7 | Fit the housing and confirm the shaft turns the impeller |
| 8 | Run on muffs and watch the telltale before launching the boat |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Shipping from Australia
| Destination | Warehouse | Note |
|---|---|---|
| Australia | Australia local warehouse | Domestic delivery, no import duty |
| New Zealand | Australia local warehouse | Short transit, customs may apply |
| Pacific islands | Australia local warehouse | Tracked shipping available |
Before You Buy
- Check the number on the old impeller, 777817 and 386084 are the same part
- Check the horsepower and year against the table
- Check the driveshaft for scoring and the liner for grooves
- Change the impeller with the gear oil, in one job
- This is the impeller only, the liner, plate and gaskets are not included
- Flush the motor after every salt water trip
- 30-Day Easy Returns
- Ships from our Australia local warehouse
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