Water Pump Repair Kit – Fits Mercury/Tohatsu/Nissan 25-40 HP (Replaces 361873220, 853792A07)
Water Pump Repair Kit – Fits Mercury/Tohatsu/Nissan 25-40 HP (Replaces 361873220, 853792A07) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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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.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Water Pump Repair Kit – Fits Mercury/Tohatsu/Nissan 25-40 HP (Repla...
Water Pump Repair Kit – Fits Mercury/Tohatsu/Nissan 25-40 HP (Replaces 361873220, 853792A07) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Repair Kit – Fits Mercury/Tohatsu/Nissan 25-40 HP is a complete aftermarket solution for maintaining your engine's cooling system. It is designed for specific Mercury Marine 25-30 HP 4-Stroke EFI engines (2002 and later), as well as a range of Tohatsu and Nissan 25-40 HP 2-Stroke (1996-2005) and 25-30 HP 4-Stroke engines (2002-2017).
This kit provides a direct interchange for Mercury part numbers 853792A07, 853792A1, and 853792T01, along with Tohatsu/Nissan references 361-87322-0, 361873220M, and 361873220.
- Engineered for direct OEM-replacement installation.
- Constructed with marine-grade materials to meet or exceed OEM specifications.
- Produced in an ISO 9002 certified factory to ensure quality and reliability.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury Marine | 853792A07 |
| Mercury Marine | 853792A1 |
| Mercury Marine | 853792T01 |
| Tohatsu / Nissan | 361-87322-0 |
| Tohatsu / Nissan | 361873220M |
| Tohatsu / Nissan | 361873220 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury Marine Owners: This kit fits specific 25 HP and 30 HP 4-Stroke EFI models from 2002 and newer, identified by serial number range. Please check your engine's serial number plate.
For Tohatsu & Nissan Owners: This kit covers a wide variety of 2-stroke and 4-stroke models. Verify your model number and year to ensure correct fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | Sea Pro | 25 | 4-Stroke | 0R051710 & Up | 853792A07 | |
| Mercury | EFI Standard | 25 | 4-Stroke | 0R106999 & Up | 853792A07 | |
| Mercury | EFI JET | 25 | 4-Stroke | 0R165086 & Up | 853792A07 | |
| Mercury | EFI Standard | 30 | 4-Stroke | 0R106999 & Up | 853792A07 | |
| Tohatsu/Nissan | M25C2, NS25C2 | 25 | 2-Stroke | 1996–2005 | 361-87322-0 | |
| Tohatsu/Nissan | M25C3, NS25C3 | 25 | 2-Stroke | 2002–2005 | 361-87322-0 | |
| Tohatsu/Nissan | M30A3, NS30A3 | 30 | 2-Stroke | 1996–2002 | 361-87322-0 | |
| Tohatsu/Nissan | NS35C, M35 | 35 | 2-Stroke | 2002 | 361-87322-0 | |
| Tohatsu/Nissan | NS40C, NS40C2, M40C | 40 | 2-Stroke | 1996–2004 | 361-87322-0 | |
| Tohatsu/Nissan | 4-Stroke Models | 25-30 | 4-Stroke | 2002–2017 | 361-87322-0 |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Installation
- Direct OEM Replacement
- Fuel Type
- Gasoline
- Housing Material
- Marine-grade Materials (OEM Specification)
- Warranty
- Standard Manufacturer Warranty
- Other Technical Attributes
- Produced in ISO9002 certified factory
Installation Notes
- Disconnect the negative battery terminal for safety.
- Place a drain pan under the lower unit and remove the gearcase oil drain screw to empty the oil.
- Remove the bolts securing the lower unit (gearcase) to the engine's midsection and carefully lower it.
- Unbolt and remove the old water pump housing to access the impeller and wear plate.
- Clean any gasket residue from the mounting surfaces and inspect the driveshaft for wear or damage.
- Install the new gaskets, wear plate, impeller, and keyway from the kit. Ensure the impeller vanes are oriented correctly.
- Fasten the new water pump housing, ensuring bolts are torqued to manufacturer specifications.
- Reinstall the lower unit, making sure the driveshaft and shift shaft align properly.
- Refill the gearcase with the correct type and amount of marine gear oil.
- Reconnect the battery, start the engine in a water source (using muffs or in the water), and confirm a steady water stream from the tell-tale outlet.
Troubleshooting & FAQ
How do I know if this kit fits my engine?
First, check the "Engine & Model Compatibility" table. Your engine's brand, model, horsepower, and year/serial number should match a row in the table. Second, if you know your existing part's number, confirm it is listed in the "Part Number Matrix."
What are the signs of a failing water pump?
The most common symptoms are engine overheating at idle or low speeds, a weak or non-existent water stream from the "tell-tale" outlet, or an alarm from your engine's warning system. During inspection, a cracked, brittle, or melted impeller is a clear sign of failure.
How often should I replace my water pump impeller?
For preventative maintenance, we recommend inspecting the impeller annually and replacing it every 1-2 years or every 100-200 hours of use. Operation in sandy, silty, or saltwater environments may require more frequent replacement.
Is this an OEM or aftermarket part?
This is an aftermarket replacement part, not an original equipment manufacturer (OEM) component. It has been engineered to meet or exceed OEM-level specifications using comparable, high-quality materials and is manufactured in an ISO 9002 certified facility with strict quality controls.
How fast is shipping?
We offer fast worldwide shipping, with typical transit times of 5–15 days for standard delivery. Standard shipping is free to most locations. Where available, expedited shipping options and costs will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter a problem, contact our support team with your order number. We accept returns for unused items in their original packaging within our standard return period. Please see our full policy page or contact us for details.
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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