Water Pump Repair Kit – Fits Mercury & Mariner 2-Stroke 15–25 HP & 4-Stroke 9.9–15 HP (Replaces 99157T2, 85098A2, 99157A2)
Water Pump Repair Kit – Fits Mercury & Mariner 2-Stroke 15–25 HP & 4-Stroke 9.9–15 HP (Replaces 99157T2, 85098A2, 99157A2) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Water Pump Repair Kit – Fits Mercury & Mariner 2-Stroke 15–25 H...
Water Pump Repair Kit – Fits Mercury & Mariner 2-Stroke 15–25 HP & 4-Stroke 9.9–15 HP (Replaces 99157T2, 85098A2, 99157A2) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket upper water pump repair kit is designed to service the cooling-system water pump on selected Mercury and Mariner outboards, including 2-stroke 15–25 HP models and 4-stroke Bigfoot 9.9–15 HP models. The listed applications cover model years and serial-number ranges shown in the compatibility table below.
The kit is listed as a replacement for Mercury references 46-99157T2, 46-99157A2, and 46-85098A2, along with the related reference numbers 99157T2, 99157A2, and 85098A2. These numbers are provided for cross-reference; always verify the complete engine model, year, and serial number before ordering.
- Designed as a direct-fit replacement for the listed applications.
- Includes a stainless-steel pump housing and neoprene impeller.
- Includes gaskets, seals, washers, keys, O-rings, and related pump-service components listed below.
- Suitable for water-pump service when the original component and application match the listed references.
Part Number Matrix
Use the following references to compare the kit with the part numbers associated with the listed applications.
| Brand | Part Number | Related Reference |
|---|---|---|
| Mercury | 46-85098A2 | 85098A2 / 99157A2 |
| Mercury | 46-99157A2 | 99157A2 / 99157T2 |
| Mercury | 46-99157T2 | 99157T2 |
| Marinepro | 99157T2 | Aftermarket cross-reference |
| GHmarine | 99157T2 | Aftermarket cross-reference |
| UanofCn | 99157T2 | Aftermarket cross-reference |
Engine & Model Compatibility
Confirm the exact engine brand, model designation, horsepower, stroke type, year, and serial number before installation. Model families can use different components across production years and serial ranges.
| Brand | Model | Rated HP | Stroke | Years | Reference | Notes |
|---|---|---|---|---|---|---|
| Mercury | 15 (E, EH, EL, ELH) 4 | 15 | 4-Stroke | 1998 | 99157T2 | Bigfoot models |
| Mercury | 15 (MH, MLH, MLH/ALT, MLH/BF) 4 | 15 | 4-Stroke | 1998 | 99157T2 | Bigfoot models |
| Mercury | 9.9 Bigfoot | 9.9 | 4-Stroke | 1998 | 99157T2 | USA serial 0G760300–0T979999; BEL serial 0P075166–0P325499 |
| Mercury | 15 XD Bigfoot | 15 | 2-Stroke | 1997–1998 | 99157T2 | BEL serial 9927000 and up |
| Mercury | 18, 18XD | 18 | 2-Stroke | 1980–1985 | 85098A2 / 99157A2 / 99157T2 | USA serial 5837437 and up; AUS 8071973 and up; BEL 9308306 and up |
| Mercury | 20, 20XD | 20 | 2-Stroke | 1986–1987 | 99157A2 / 99157T2 | USA serial 6443973–0T800749; BEL 9415101 and up; CAN 7209533 and up |
| Mercury | 25, 25XD | 25 | 2-Stroke | 1980–1987 | 85098A2 / 99157A2 / 99157T2 | USA serial 5705532 and up; AUS 8073158 and up |
| Mercury | 25, 3-cylinder | 25 | 2-Stroke | 1997 and up | 99157T2 | USA serial 0E268781 and up |
| Mercury | 25 Sea Pro, Marathon, Super 15 | 25 | 2-Stroke | 1988–1998 | 99157T2 | USA serial 0B238464 and up; BEL 9507381 and up; CAN 0A730007 and up |
| Mariner | 15 (E, EH, EL, EL/BF, ELH, MH, MLH) 4 | 15 | 4-Stroke | 1998 | 99157T2 | Bigfoot models |
| Mariner | 15 MLA | 15 | 2-Stroke | 1994 | 99157T2 | Model code 70152374D |
| Mariner | 18, 18XD | 18 | 2-Stroke | 1980–1985 | 85098A2 / 99157A2 / 99157T2 | Verify the engine serial number |
| Mariner | 20 (E, EH, EL, M, MH, ML, MLH) | 20 | 2-Stroke | 1984–1998 | 85098A2 / 99157A2 / 99157T2 | Multiple model codes |
| Mariner | 25 (E, EH, EL, ELH, MH, ML, MLH) | 25 | 2-Stroke | 1980–1998 | 85098A2 / 99157A2 / 99157T2 | Multiple model codes |
| Mariner | 25 JET 20 | 25 | 2-Stroke | 1994–1998 | 99157T2 | Verify model and serial number |
| Mariner | 25 MH/ALT, MLH/ALT | 25 | 2-Stroke | 1994–1998 | 99157T2 | Verify model and serial number |
| Force | 25 | 25 | 2-Stroke | 1995–1998 | 99157T2 | Various serial ranges; confirm before purchase |
| Sears | Gamefisher | 25 | 2-Stroke | 1997–1998 | 99157T2 | Models 225.582500, 225.582501, 225.582591, 225.592500, and 225.592590 |
Technical Specifications
- Product Type
- Upper water pump repair kit
- Installation
- Direct-fit replacement for listed applications
- Housing Material
- Stainless steel 316
- Housing Color
- Silver/metallic
- Approximate Dimensions
- 6.2 × 4.3 × 1.9 inches (157.5 × 109.2 × 48.3 mm)
- Approximate Weight
- 0.5 lb (0.23 kg)
- Impeller Material
- Neoprene
- Other Components
- Rubber O-rings, gaskets, washers, key, seal, face plate, and water-tube guide sleeve
What's in the Box
- 1 × Pump housing assembly, reference 99157A02/99157A1
- 1 × Face plate, reference 85083
- 1 × Gasket, reference 993261
- 1 × Key, reference 8M0032838
- 1 × Seal, reference 85090001/85090
- 2 × Transparent washers, reference 12-86645-1
- 4 × Insulators, reference 23-85095
- 3 × O-rings
- 1 × Impeller, reference 47-85089/8M0024502/8508910
- 1 × Water-tube guide sleeve
- 2 × Gear-lube fill and vent screw O-rings
Component references are supplied for identification. Some parts may be unused when the kit is installed on a particular engine variation.
Installation Notes
- Disconnect the negative battery cable, remove the engine cowling, and place the outboard in neutral.
- Remove the bolts securing the lower unit to the upper leg and carefully lower the gearcase.
- Remove the old water-pump housing and note the original impeller-vane orientation.
- Clean the driveshaft and all mating surfaces, removing old gasket material and residue.
- Install the gasket, wear plate, and key. Fit the new impeller to the driveshaft while turning the shaft clockwise so the vanes seat correctly.
- Apply a light coat of suitable marine grease to the inside of the pump housing and install the housing over the impeller.
- Reinstall the lower unit, making sure the water tube, driveshaft, and shift shaft align correctly before tightening the fasteners.
- Reconnect the battery. Start the engine only in an appropriate water supply and confirm a strong, steady tell-tale stream.
Follow the service procedures and torque specifications for the exact engine model. If you are not experienced with lower-unit removal or water-pump service, use a qualified marine technician.
Troubleshooting & FAQ
How do I confirm fitment?
Compare the complete engine model, year, horsepower, stroke type, and serial number with the compatibility table. Also compare the original pump components and reference numbers before ordering.
What are the signs of a failing water-pump impeller?
Common signs include overheating at idle or low speed, a weak or intermittent tell-tale stream, no water flow, or a brittle, cracked, or deformed impeller.
How often should the impeller be inspected or replaced?
Inspect the impeller according to the engine manufacturer's maintenance schedule. More frequent inspection may be appropriate for engines used in saltwater, sandy, or silty conditions.
Is this an OEM part?
No. This is an aftermarket replacement kit intended for the listed applications and reference numbers. It is not manufactured by Mercury, Mariner, Force, or Sears.
Do the included gaskets require sealant?
Install gaskets according to the service instructions for the exact engine. Do not apply sealant to the impeller or any surface where it could restrict cooling-water flow. Use only a compatible non-hardening sealant when the engine service procedure specifically calls for one.
Why are there multiple O-rings and extra parts?
The kit covers several engine variations. Some included components may not be required for every application. Match each part with the service diagram for your exact model before installation.
What should I do after installation?
Run the engine only in a suitable water supply and check for a steady tell-tale stream, leaks, abnormal noise, or overheating. Stop the engine immediately if cooling flow is weak or absent.
Safety & Important Information
- Confirm the engine model, year, stroke type, serial number, and original component before purchase.
- Do not operate an outboard without an adequate water supply.
- Allow the engine to cool before servicing the cooling system.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended when lower-unit service experience or the correct service tools are not available.
About Sea Sierra
- Pro-Grade Standards — Marine replacement parts selected for dependable service in real-world operating conditions.
- Fast Global Fulfillment — Standard delivery options are available to many regions; delivery times vary by destination.
- Manufacturer-Direct Value — Competitive replacement-part pricing with practical application information.
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