Lower Water Pump Gasket – Fits Mercury/Mariner 25-50 HP Outboards (Replaces 27-822217)
Lower Water Pump Gasket – Fits Mercury/Mariner 25-50 HP Outboards (Replaces 27-822217) is backordered and will ship as soon as it is back in stock.
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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.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Lower Water Pump Gasket – Fits Mercury/Mariner 25-50 HP Outboards (...
Product Details
This high-quality Lower Water Pump Gasket is designed for Mercury/Mariner outboard engines from 25 to 50 HP (2-Stroke & 4-Stroke models, 1994–present), ensuring a precise seal for the lower water pump assembly.
It serves as a direct replacement for Mercury part numbers 27-822217 and 8M0214956, as well as Quicksilver 27-822217.
- Installs between the upper and lower water pump housing components.
- Critical for preventing leaks and maintaining cooling system integrity.
- Engineered to meet or exceed OEM specifications for fit and function.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury | 27-822217 | 8M0214956 |
| Quicksilver | 27-822217 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury & Mariner Engines: This gasket fits a wide range of 2-stroke, 4-stroke, and 3-cylinder models from 1994 to the present, including Jet, Bodensee, and Bigfoot variations.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 25 | 25 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 30 | 30 | 2-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 30 | 30 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 30 JET | 30 | 3-Cylinder | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 40 | 40 | 2-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 40 | 40 | 3-Cylinder | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 40 | 40 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 45 BODENSEE | 45 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 50 | 50 | 3-Cylinder | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 50 | 50 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
| Mercury | 50 BIGFOOT | 50 | 4-Stroke | 1994–Present | 27-822217/8M0214956 | Superseded to 8M0214956 |
Technical Specs
- Product Type
- Lower Water Pump Gasket
- Installation Location
- Between water pump housing components
- Application
- Used in lower water pump assembly
- Product Dimensions
- 16.0" L x 10.0" W x 0.3" H
What’s in the Box
- 1 x Gasket (Replaces OEM 27-822217 / 8M0214956)
Installation Notes
- Disconnect the negative battery terminal and remove the engine cowling.
- Shift the outboard into neutral and remove the bolts securing the lower unit (gearcase).
- Carefully separate and lower the gearcase to expose the water pump assembly.
- Remove the bolts from the water pump cover and lift the cover off.
- Take note of the old gasket's position, then remove and discard it.
- Thoroughly clean the mating surfaces on the pump housing and gearcase, removing all old gasket residue.
- Position the new gasket correctly on the water pump housing.
- Reassemble the water pump components in reverse order, ensuring correct alignment.
- Torque all bolts to the manufacturer's recommended specifications.
- Reinstall the lower unit, making sure the driveshaft, shift shaft, and water tube are properly aligned.
- Secure the gearcase bolts and reconnect the battery terminal.
- Start the engine using a water supply (flushing muffs) and check for leaks and proper water outflow from the tell-tale port.
Troubleshooting & FAQ
How do I know if this gasket will fit my engine?
This gasket is specifically for Mercury/Mariner 25-50 HP outboards (1994–present). The most reliable way to confirm fitment is to check for part number 27-822217 or 8M0214956 in your engine's service manual or parts diagram. You can also compare your old gasket's shape to our product photos.
What are the signs of a failing water pump gasket?
Common symptoms include the engine overheating at idle or low speeds, a weak or inconsistent water stream from the 'telltale' outlet, or visible water leaks around the seam where the lower unit meets the midsection.
How often should water pump gaskets be replaced?
It's standard practice to replace all water pump gaskets and the impeller as part of a complete water pump service. This is typically recommended every 1–2 years or every 100–200 hours of use, especially in saltwater environments.
The part number on my old gasket is 27-822217. Will this fit?
Yes. Part number 8M0214956 is the official supersession for 27-822217, meaning it is the current, direct replacement. This part is designed to fit in place of both numbers.
Can I reuse my old gasket?
No. Gaskets are single-use components designed to crush and create a seal. Reusing an old gasket will likely result in leaks, leading to poor cooling performance and potential engine damage.
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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