Water Pump Impeller Kit 46-96148A8 MerCruiser Alpha One Gen 1 MR R Sierra 18-3319
Water Pump Impeller Kit 46-96148A8 MerCruiser Alpha One Gen 1 MR R Sierra 18-3319
Product Overview
Complete water pump impeller kit for MerCruiser Alpha One Gen 1, MR and R sterndrives, and for Mercury 150 HP to 225 HP V6 outboards. It replaces Mercury 46-96148A8 and 46-44292A3 and crosses to Sierra 18-3319, and it ships as one full kit in a 150 mm x 100 mm x 80 mm box at 469 g.
The kit is the whole pump, not just the rubber. The box contains the housing 46-96148A1, a 2.350 inch outside diameter pump base, the impeller, the water tube guide 23-29804, the stainless wear plate 32435, the three base gaskets, the two wear plate gaskets, the water tube grommet and every O ring and drain washer the job needs.
That matters because most impeller failures on these drives are not the rubber alone. A scored wear plate or a housing with a worn cam will destroy a new impeller in a season, and a pump base that has been run hot will not hold pressure even with perfect blades.
Fitment covers the Alpha One Gen 1, MR and R sterndrives, plus the Mercury V6 outboards listed in the table below: the 150HP and 150HP XS six cylinder motors, the V150 Carb in XR2, XR4 and XR6 form, the V175 in carb, EFI and DFI, the V200 carb and EFI in 2.5 litre form, and the V220 LASER at 2.4 litre. The wider Mercury V6 range from 150 to 225 HP uses the same 2.350 inch pump base, but the serial number decides.
Specifications
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Complete water pump impeller kit |
| Main Part Numbers | 46-96148A8, 46-44292A3 |
| Pump Housing | 46-96148A1 |
| Pump Base | 2.350 inch outside diameter |
| Impeller Numbers | 46-89984, 47-89984, 47-89984T3, 47-89984T4 |
| Sierra Cross Reference | 18-3319 |
| Fits | MerCruiser Alpha One Gen 1, MR and R sterndrives |
| Also Fits | Mercury V6 outboards, 150HP to 225HP |
| Kit Type | Housing, base, impeller, plates, guide and seals |
| Package Contents | Complete kit, see the list below |
| Net Weight | 469 g including packaging |
| Pack Size | 150 mm x 100 mm x 80 mm |
| Pack Size In Inches | 5.91 in x 3.94 in x 3.15 in |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| Mercury | 46-96148A8 |
| Mercury | 46-44292A3 |
| Mercury | 46-96148A1, 46-96148T1 (pump housing) |
| Mercury | 42579A4, 44292A4, 48747A3, 57234A3 |
| Mercury | 46-89984, 47-89984, 47-89984T3 |
| Mercury | 47-89984T4, 47-899844, 47-30221 |
| Mercury | 47-65960, 47-8546065 |
| Mercury | 47-803631T, 47-F694065 |
| Mercury | 23-29804, 32-29804T (water tube guide) |
| Mercury | 32435 (wear plate) |
| Mercury | 56654 |
| Sierra | 18-3319 |
Compatible Engines
| Engine Or Drive | Note |
|---|---|
| MerCruiser Alpha One Gen 1 | Sterndrive, 2.350 inch OD pump base |
| MerCruiser MR | Sterndrive, 2.350 inch OD pump base |
| MerCruiser R | Sterndrive, 2.350 inch OD pump base |
| Mercury 150HP | 6 cylinder |
| Mercury 150HP XS | 6 cylinder |
| Mercury V150 | Carb, XR2, XR4, XR6 |
| Mercury V175 | Carb, EFI, DFI |
| Mercury V200 | Carb and EFI, 2.5 litre |
| Mercury V220 LASER | 2.4 litre |
| Mercury V6 range | 150 to 225 HP, confirm the serial number |
What's Included
| Component | Part Number Or Size | Qty |
|---|---|---|
| Pump housing | 46-96148A1 | 1 |
| Pump base | 2.350 inch outside diameter | 1 |
| Impeller | 46-89984, 47-89984, 47-89984T3 | 1 |
| Water tube guide | 23-29804, 32-29804T | 1 |
| Wear plate | 32435, stainless | 1 |
| Pump base to gear housing gasket | 27-42631-1 | 1 |
| Pump base to gear housing gasket | 27-85610-1 | 1 |
| Pump base to gear housing gasket | 27-32438 | 1 |
| Wear plate gasket, lower | 27-85608-1 | 1 |
| Wear plate gasket, upper | 27-85609-1 | 1 |
| Water tube grommet | 26-38970 | 1 |
| Oil passage seal | 26-45577 | 1 |
| Drain screw washer | 12-19183 | 2 |
| O ring | 25-30613 | 1 |
| O ring | 25-33145 | 1 |
| O ring | 25-30224 | 1 |
| O ring | 25-90011 | 1 |
| O ring | 25-38099 | 1 |
| O ring | 25-30271 | 1 |
| Screw and washer set | As supplied with the housing | 1 set |
Signs The Pump Needs Rebuilding
| What You See | What It Means | What To Do |
|---|---|---|
| Overheat at cruise, fine at idle | Blades worn or set | Fit the full kit |
| Weak tell tale | Flow dropped through a scored plate | Fit the full kit |
| Impeller shredded, rubber in the hose | Blades broke up in the pump | Fit the full kit and flush the system |
| New impeller fails in weeks | Housing cam or wear plate worn | Fit the full kit, not just the impeller |
| Water in the gear lube | Pump base seals failed | Fit the full kit and pressure test the drive |
| Temperature climbs after a lay up | Impeller set over winter | Fit the full kit |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the drive model and serial number against the table above |
| 2 | Drain the drive and split the lower unit |
| 3 | Take the pump housing off and lift out the impeller |
| 4 | Check the drive shaft, the shaft key and the housing cam for wear |
| 5 | Scrape the base and gear housing faces clean, do not gouge them |
| 6 | Fit the new base with its gasket and torque it evenly |
| 7 | Fit the wear plate and gasket, then fold the impeller blades in the direction of rotation |
| 8 | Refit the housing with a new gasket and check the shaft turns freely |
| 9 | Refill the drive, pressure test and run on muffs to confirm the tell tale |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Boxed, 150 mm x 100 mm x 80 mm |
Before You Buy
- Replaces Mercury 46-96148A8 and 46-44292A3
- Crosses to Sierra 18-3319
- Fits MerCruiser Alpha One Gen 1, MR and R sterndrives
- Fits Mercury V6 outboards from 150HP to 225HP, serial number decides
- Full kit: housing 46-96148A1, 2.350 inch pump base, impeller, wear plate 32435
- Includes water tube guide 23-29804 and grommet 26-38970
- All gaskets, O rings and drain washers in the box
- 469 g with packaging, box 150 mm x 100 mm x 80 mm
- 30-Day Easy Returns
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Boat Owners' Review
Before You Buy
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