Upper Water Pump Repair Kit – Fits MerCruiser Alpha One Gen II & Vazer Drives (Replaces 817275Q05)
Upper Water Pump Repair Kit – Fits MerCruiser Alpha One Gen II & Vazer Drives (Replaces 817275Q05) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Upper Water Pump Repair Kit – Fits MerCruiser Alpha One Gen II &...
Product Details
This is a complete Upper Water Pump Repair Kit designed for MerCruiser Alpha One Gen II sterndrive units (1991 and newer) and all MerCruiser Vazer drive applications. The kit is engineered to restore the upper section of the water pump, ensuring optimal cooling system performance and preventing engine overheating.
This kit provides a direct interchange for Mercury/Quicksilver part numbers 817275Q05, 817275A3, 817275A4, and 817275Q4.
- Easy installation with common hand tools.
- Includes all essential gaskets, o-rings, and hardware for a complete upper pump rebuild.
- Designed for higher flow rates and improved cooling efficiency.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury / Quicksilver | 817275A3 | 817275Q05 |
| Mercury / Quicksilver | 817275A4 | 817275Q05 |
| Mercury / Quicksilver | 817275Q4 | 817275Q05 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury/MerCruiser owners, this kit fits the popular Alpha One Gen II sterndrive and Vazer drive. Please verify your specific engine model and serial number range if applicable.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | Alpha One Gen II | Various | 4-Stroke | 1991 and newer | 817275Q05 | Standard rotation |
| MerCruiser | Vazer | Various | 4-Stroke | All years | 817275Q05 | |
| Mercury | 225 (3.0L EFI) | 225 | 4-Stroke | 0G438000 and up | 817275Q05 | G/HSG drive std/counter |
| Mercury | 250 (3.0L EFI) | 250 | 4-Stroke | 0G438000 and up | 817275Q05 | G/HSG drive std/counter |
Technical Specs
- Product Type
- Upper Water Pump Repair Kit
- Installation
- Direct replacement with common tools
- Housing Material
- Various materials (metal & rubber components)
- Housing Color
- Silver/metallic
- Dimensions
- 18.0 x 11.0 x 12.0 inches
- Weight
- 0.73 kg (1.38 lbs)
- Warranty
- OEM Mercury manufacturer warranty
- Other Technical Attributes
- Designed for higher flow rates and cooling flow
What’s in the Box
- 1 x Upper Water Pump Repair Kit (Replaces 817275Q05) including:
- Gaskets
- O-ring
- Plates
- Impeller
- Key
- Water guide fittings
- Upper housing
Installation Notes
- Disconnect the battery cables from the battery before starting work.
- Remove the sterndrive unit from the transom assembly.
- Place the drive in a suitable stand and drain the gearcase lubricant.
- Unbolt and carefully separate the upper and lower units of the drive.
- Remove the old water pump housing, impeller, and wear plates. Note the orientation of all parts.
- Thoroughly clean all mating surfaces, removing any old gasket material or sealant.
- Install the new wear plate, gaskets, and impeller from the kit. Use a suitable lubricant on the impeller.
- Install the new upper housing and torque the bolts to the manufacturer's specification.
- Reassemble the drive unit, reinstall it on the boat, and refill the gearcase with fresh lubricant.
- Reconnect the battery and test run the engine on a water supply, checking for proper water circulation and leaks.
Troubleshooting & FAQ
How do I know if this kit fits my MerCruiser drive?
This kit is specifically for MerCruiser Alpha One Generation II drives (made from 1991 onwards) and all Vazer drives. It is not compatible with Alpha One Gen I. Always check your drive's model and year before ordering.
What are the signs of a failing water pump?
Common symptoms include the engine overheating at idle or low speeds, a weak or no water stream from the "telltale" outlet, and visible cracking or damage on the old impeller upon inspection.
How often should the water pump impeller be replaced?
As a general maintenance guideline, the impeller should be inspected annually and replaced every 1-2 years, or every 100-200 hours of use, depending on operating conditions (e.g., saltwater vs. freshwater).
Can I install this kit myself?
Yes, installation can be performed by a mechanically inclined individual with common tools. It involves separating the sterndrive's upper and lower units. However, if you are not comfortable with this process, professional installation is recommended.
Does this kit include everything I need for the upper pump?
Yes, this is an 11-piece kit containing the upper housing, impeller, key, plates, gaskets, o-rings, and water guide fittings required for a standard upper water pump service.
Is any special grease or sealant needed for installation?
It is highly recommended to use a marine-grade grease or soapy water to lubricate the inside of the pump housing and the new impeller to prevent damage during the first dry start.
OEM vs. Aftermarket?
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.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
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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