Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5)
Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces...
Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5) is backordered and will ship as soon as it is back in stock.
Product Details
This is a complete Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5), designed for various EFI, DFI, Carb, Pro XS, and 4-Stroke outboard engines. It provides a reliable solution for maintaining your engine's cooling system for optimal performance.
It serves as a direct replacement for Mercury part numbers 817275A5, 817275Q05, 817275A6, 847275A5 and aftermarket parts from Sierra (18-3147), GLM (12098), and EMP (46-46502).
- Engineered for direct OEM replacement installation.
- Complete kit includes housing for a full lower unit water pump assembly rebuild.
- Designed to restore cooling efficiency and prevent overheating.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 817275A5 |
| Mercury | 817275Q05 |
| Mercury | 817275A6 |
| Mercury | 847275A5 |
| Sierra | 18-3147 |
| GLM | 12098 |
| EMP | 46-46502 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This component is specifically designed for Mercury and Mariner outboard engines.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury/Mariner | 200 DFI | 200 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 200 EFI | 200 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 225 Carb | 225 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 225 DFI | 225 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 225 EFI | 225 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 225 Pro XS | 225 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 250 | 250 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 3.0L EFI DFI | 200-250 | 4-Stroke | 817275A5 | |
| Mercury/Mariner | 300 HP | 300 | 4-Stroke | 817275A5 | Mentioned in Amazon listing |
Technical Specs
- Product Type
- Water Pump Impeller Rebuild Kit with Housing
- Installation
- Direct OEM replacement
- Other Technical Attributes
- For lower unit water pump assembly
What’s in the Box
- 1 x Water Pump Rebuild Kit (817275A5)
- 1 x Seal Kit-OBM (816575A2)
- 1 x Upper Water Pump Gasket (8172771)
- 1 x Aluminum Cover Gasket (430331)
Installation Notes
- Disconnect the battery and ensure the engine is in the OFF position.
- Drain the gearcase lubricant from the lower unit.
- Remove the lower unit from the outboard motor by unbolting it from the midsection.
- Place the lower unit on a workbench. Unbolt and remove the old water pump housing.
- Remove the old impeller, key, gaskets, and seals. Clean all mating surfaces thoroughly.
- Install the new gaskets, seals, wear plate, and impeller key from the kit.
- Slide the new impeller onto the driveshaft, ensuring the key is aligned.
- Lubricate the inside of the new housing and install it over the impeller, turning the driveshaft clockwise to seat the vanes.
- Secure the new housing with the provided bolts and torque to the manufacturer's specifications.
- Reinstall the lower unit, refill with gearcase lubricant, and reconnect the battery.
- Test the engine's cooling system using a flush attachment before returning to the water.
Troubleshooting & FAQ
How do I know if my water pump impeller is failing?
Common signs of a failing impeller include a weak or non-existent water stream from the "tell-tale" port, engine overheating alarms, and reduced engine performance. It is recommended to inspect the impeller annually.
What is the recommended replacement interval for this kit?
For optimal reliability, most engine manufacturers recommend replacing the water pump impeller every 100-200 operating hours or at least once a year, whichever comes first, especially for boats operated in saltwater or sandy conditions.
Will this kit fit models outside the 200-250 HP range?
This kit is specifically designed for the Mercury/Mariner 200-250 HP engine range. While it may fit a 300 HP model, always verify your engine's specific part number before ordering to ensure compatibility.
What is the difference between an OEM part and this aftermarket kit?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
What are your shipping speeds and costs?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
What is the warranty and return policy?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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