Water Pump Impeller with Key 47-42038Q02 47-42038 28-42376A2 for Mercury Mariner 6 8 9.9 10 15 HP
Water Pump Impeller with Key 47-42038Q02 47-42038 28-42376A2 for Mercury Mariner 6 8 9.9 10 15 HP
Product Overview
Water pump impeller with drive key for Mercury and Mariner outboards of 6, 8, 9.9, 10 and 15 HP, the small gearcase impeller with 6 blades, 58.66 mm outside diameter and a 12.68 mm shaft insert. It replaces Mercury 47-42038 and the -1, -2 and Q02 suffixes, and comes with the key 28-42376A2.
It fits the two cylinder two strokes from USA serial 0A197112 and Belgium serial 9461526 onwards, the Mercury four stroke 8 and 9.9 HP up to 2004 and the 15 HP up to 2005, plus the Force and Sears 1998 9.9 and 15 HP motors with the standard gearcase.
The key is the part that gets lost. Without it the impeller spins on the shaft, the motor overheats within minutes and the shaft end is often damaged. This kit includes the key, so the pump goes back together in one job.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Outboard water pump impeller with key |
| Blades | 6 |
| Outside Diameter | 58.66 mm |
| Shaft Insert Diameter | 12.68 mm |
| Height | 11.54 mm |
| Hub | Plastic |
| Net Weight | 11 g, 24 g with packaging |
| Pack Size | 15 x 18 x 5 cm |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| Mercury / Mariner | 47-42038, 47-42038-1, 47-42038-2, 47-42038Q02 |
| Impeller key | 28-42376A2 |
| CEF | 500318 |
| Mallory | 9-45039 |
| Sierra | 18-3062 |
| AMIC | 777-1309 |
Compatible Engines
| Model | Condition | Note |
|---|---|---|
| Mercury / Mariner 6 HP | 2 cylinder 2-stroke | USA 0A197112 and above |
| Mercury / Mariner 8 HP | 2 cylinder 2-stroke | USA 0A197112 and above |
| Mercury / Mariner 9.9 HP | 2 cylinder 2-stroke | USA 0A197112 and above |
| Mercury / Mariner 10 HP | 2 cylinder 2-stroke | BEL 9461526 and above |
| Mercury / Mariner 15 HP | 2 cylinder 2-stroke | USA 0A197112 and above |
| Mercury 8 and 9.9 HP four stroke | 2004 and prior | Standard gearcase |
| Mercury 15 HP four stroke | 2005 and prior | Standard gearcase |
| Force and Sears 9.9 and 15 HP | 1998 | Standard gearcase |
What's Included
| Component | Reference | Qty |
|---|---|---|
| Water pump impeller, 6 blade | 47-42038Q02 pattern | 1 |
| Impeller drive key | 28-42376A2 | 1 |
| Housing and plate | Not included | 0 |
Impeller and Key Together
| What You Find | What It Means | What To Do |
|---|---|---|
| Key missing from the shaft | Impeller will not drive | Fit the key supplied in this kit |
| Key flat on one side | Impeller has been spinning | Check the shaft slot for damage |
| Hub spun in the rubber | Impeller failed from a dry start | New impeller, this cannot be repaired |
| Insert bore opened up | Worn shaft or wrong part | Measure the insert, this is 12.68 mm |
| Blades set flat in the housing | Stored tilted up | Renew before the season |
| Housing liner grooved | Grit in the pump | New liner and plate with the impeller |
Small Gearcase Outboards in Salt Water
| How the Motor Is Used | Effect on the Impeller | What To Do |
|---|---|---|
| Tender or tinny, salt water | Salt dries on the blades | Flush on muffs after every trip |
| Sand and mud ramps | Grit scores the liner and plate | Check the liner each season |
| Tilted up between trips | Pump drains and starts dry | Lower fully before starting |
| Long idle up a creek | Blades ride one side of the cam | Run up to cruise on the way back |
| Boat ashore over winter | Blades take a set | Renew before the season starts |
| Four stroke 8 and 9.9 | Same pump as the two strokes | Check the year, 2004 and prior |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the serial number, USA 0A197112 and Belgium 9461526 and above take this impeller |
| 2 | Drop the gearcase and check the old key, it is often still in the shaft slot |
| 3 | Measure the old impeller, this one is 58.66 mm across and 11.54 mm high |
| 4 | Clean the housing liner and the plate, grit wears a new impeller fast |
| 5 | Grease the liner and fold the blades in the running direction |
| 6 | Fit the key, then slide the impeller down square onto the shaft |
| 7 | Fit the plate, gasket and housing, tighten evenly |
| 8 | Run on muffs and watch the telltale before the boat is launched |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Check the number on the old impeller, 47-42038 and the -1, -2 and Q02 suffixes are the same part
- Fits Mercury and Mariner 6, 8, 9.9, 10 and 15 HP two strokes from the serial numbers listed
- Also fits Mercury four stroke 8 and 9.9 HP to 2004 and 15 HP to 2005
- The drive key 28-42376A2 is included
- This is the impeller and key, the housing and plate are not included
- Fold the blades in the running direction before fitting
- 30-Day Easy Returns
- Ships from our warehouse with tracking
Couldn't load pickup availability
Boat Owners' Review
Before You Buy
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