Water Pump Repair Kit – Fits Mercury Marine 25-30 HP (Replaces 853792A07)
Water Pump Repair Kit – Fits Mercury Marine 25-30 HP (Replaces 853792A07) 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 Marine 25-30 HP (Replaces 8537...
Water Pump Repair Kit – Fits Mercury Marine 25-30 HP (Replaces 853792A07) is backordered and will ship as soon as it is back in stock.
Product Details
This Mercury Water Pump Repair Kit 8M0208905 is designed for Mercury Marine 25-30 HP, 4-Stroke EFI outboard engines with serial numbers 0R106999 and above. It serves as a complete maintenance package to ensure optimal engine cooling and performance, also referred to as a "Complete Maintenance Service Kit" as it includes additional service components beyond the water pump itself.
This kit is a direct replacement for Mercury part numbers 853792A07 and 8M0208905, and provides an interchange for Sierra 18-43175 and QuickMarine 8M0208905.
- Engineered for direct replacement to ensure a precise fit and straightforward installation.
- Includes a complete water pump kit, thermostat, oil filter, fuel filter, and necessary gaskets.
- Combines essential service components for comprehensive preventative maintenance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By | Notes |
|---|---|---|---|
| Mercury Marine | 853792A07 | 8M0208905 | Original OEM part number. |
| Mercury Marine | 8M0208905 | Current OEM part number. | |
| Sierra | 18-43175 | Aftermarket cross-reference. | |
| QuickMarine | 8M0208905 | Aftermarket cross-reference. |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury Marine | Outboard | 25 | 4-Stroke EFI | 0R106999 and above | 853792A07/8M0208905 | For serial numbers 0R106999 and above |
| Mercury Marine | Outboard | 30 | 4-Stroke EFI | 0R106999 and above | 853792A07/8M0208905 | For serial numbers 0R106999 and above |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Installation
- Direct replacement
- Housing Material
- Metal, Plastic, Rubber
- Weight
- 0.23 lb (0.10 kg)
- Warranty
- 1 Year (QuickMarine), OEM warranty may vary
- Other Technical Attributes
- Complete kit includes impeller, pump housing, face plate, gaskets, seals, and o-rings
What’s in the Box
- 1 x Water Pump Impeller Kit (Replaces 8M0208905, 853792A07)
- 1 x Impeller (345-65021)
- 1 x Insert Cup (161572)
- 1 x Wear Plate (161592)
- 1 x Key (28-161551)
- 1 x Gasket (27-161602)
- 1 x Gasket (27-161582)
- 4 x Bolt (910103-5652)
- 1 x Thermostat Kit (8M0119207, 8M0214960)
- 1 x Fuel Filter (8M0162831, Sierra 18-7913)
- 1 x Oil Filter (8M0162831, Sierra 18-7913)
- 1 x Cotter Pin (8150264)
- 3 x Drain Gaskets (26-8M0007119, 8M0204693)
Installation Notes
- Disconnect the battery terminals to prevent accidental starting.
- Place a drain pan under the lower unit and remove the gear lube drain/fill screws to drain the oil.
- Remove the propeller assembly.
- Unbolt and carefully lower the gearcase (lower unit) from the outboard's midsection.
- Remove the old water pump housing, impeller, and associated gaskets and seals.
- Thoroughly clean the driveshaft and all mating surfaces where the new pump will sit.
- Assemble the new water pump kit components, starting with the base gasket, wear plate, and impeller.
- Apply a light coat of marine grease to the inside of the housing and slide it over the new impeller.
- Install the new seals and gaskets, ensuring everything is properly seated.
- Carefully guide the lower unit back into place, aligning the driveshaft, shift shaft, and water tube.
- Bolt the gearcase securely and reinstall the propeller assembly.
- Refill the lower unit with the correct gear lube, install new drain screw gaskets, and test the engine using a flush device to confirm water flow.
Troubleshooting & FAQ
How do I know if this kit fits my 25 HP Mercury engine?
This kit is specifically for 25 and 30 HP 4-Stroke EFI models with a serial number of 0R106999 or higher. It is critical to verify your engine's serial number before ordering to ensure compatibility.
What are the signs of a failing water pump?
Common signs include the engine running hotter than normal, an audible alarm if your engine has one, or a weak/non-existent water stream from the tell-tale outlet port. Upon inspection, a worn, brittle, or melted impeller is a definitive sign of failure.
How often should the water pump be serviced?
As a general guideline, we recommend inspecting the impeller annually and replacing the entire water pump kit every 2-3 years or 200-300 hours of operation, whichever comes first. This interval can be shorter in saltwater or high-debris environments.
Is this just a water pump kit or a full service kit?
This is a comprehensive maintenance kit. In addition to the complete water pump components, it includes a thermostat, fuel filter, oil filter, and drain gaskets for a more thorough service, making it an excellent value.
The same part number (8M0162831) is listed for both the fuel and oil filter. Is this an error?
No, this is correct based on our supplier information. For the applications this kit covers, the same filter part number (or its aftermarket equivalent) is specified for both fuel and oil filtration.
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.
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