Gear Housing Seal Kit – Fits Mercury/Mariner/Force 25-50 HP (Replaces 823547A2)
Gear Housing Seal Kit – Fits Mercury/Mariner/Force 25-50 HP (Replaces 823547A2) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Gear Housing Seal Kit – Fits Mercury/Mariner/Force 25-50 HP (Replac...
Product Details
This aftermarket Gear Housing Seal Kit is designed for a wide range of Mercury Marine, Mariner, and Force outboard engines. It fits most 2-stroke and 4-stroke models from 25 to 50 HP manufactured between 1995 and 2006.
It serves as a direct replacement for Mercury part numbers 823547A1 and 823547A2, as well as aftermarket equivalents from GLM (87514), SEI (95-263-11K), and Pro Marine (823547A2).
- Designed for direct OEM replacement of the lower unit gear housing seals.
- Made from durable rubber and plastic compounds to withstand the marine environment.
- Includes all standard seals required for a comprehensive gearcase reseal.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 823547A1 |
| Mercury | 823547A2 |
| GLM | 87514 |
| SEI | 95-263-11K |
| Pro Marine | 823547A2 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury models, it is critical to verify your engine's serial number against the ranges provided in the 'Notes' column for an exact match.
These tables cover common Force and Mariner models. Please check your specific model variant and year for proper fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 25 | 25 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G590000 THRU 0G760299, 0G760300 THRU 0T408999, 0P017000 THRU 0P153499, 9973100 THRU 0P016999 |
| Mercury | 30 | 30 | 2-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T979999, 0P017000 THRU 0P325499, 0P325500 & Up, 0T980000 THRU 0T999999, 1B000001 & Up |
| Mercury | 30 | 30 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T408999, 0P017000 THRU 0P153499 |
| Mercury | 30 JET | 30 | 3-Cylinder | 1997–2006 | 823547A2 | Fits 0G590000 THRU 0G760299, 9973100 THRU 0P016999, 0G760300 THRU 0T408999, 0P017000 THRU 0P153499 |
| Mercury | 40 | 40 | 2-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T979999, 0P017000 THRU 0P325499, 0P325500 & Up, 0T980000 THRU 0T999999, 1B000001 & Up |
| Mercury | 40 | 40 | 3-Cylinder | 1997–2006 | 823547A2 | Fits 0P325500 & Up, 0T980000 THRU 1B208418, 0T980000 THRU 1B209735, 0G590000 THRU 0G760299, 9973100 THRU 0P016999, 0G760300 THRU 0T979999, 0P017000 THRU 0P325499 |
| Mercury | 40 | 40 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T408999, 0P017000 THRU 0P153499 |
| Mercury | 40 ITALY | 40 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T178499, 0P017000 THRU 0P094499 |
| Mercury | 45 BODENSEE | 45 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T178499, 0P017000 THRU 0P094499 |
| Mercury | 45 ELPT | 45 | 4-Stroke | 1997 | 823547A2 | Fits 1F45412TF |
| Mercury | 50 | 50 | 3-Cylinder | 1997–2006 | 823547A2 | Fits 0P325500 & Up, 0T980000 & Up, 1B000001 & Up, 0G590000 THRU 0G760299, 9973100 THRU 0P016999, 0G760300 THRU 0T979999, 0P017000 THRU 0P325499 |
| Mercury | 50 | 50 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T178499, 0P017000 THRU 0P094499 |
| Mercury | 50 BIGFOOT | 50 | 4-Stroke | 1997–2006 | 823547A2 | Fits 0G760300 THRU 0T178499, 0P017000 THRU 0P094499 |
| Mercury | 50 EL | 50 | 4-Stroke | 1998 | 823547A2 | Fits 1F50352UD |
| Mercury | 50 ELHPT | 50 | 4-Stroke | 1996–1998 | 823547A2 | Fits 1F50411SD, 1F50411TD, 1F50411UD, 1F50411UN |
| Mercury | 50 ELPT | 50 | 4-Stroke | 1995–1998 | 823547A2 | Fits 1F50412RD, 1F50412SD, 1F50412SF, 1F50412TD, 1F50412UD, 1F50412UN |
| Mercury | 50 ELPT/BF | 50 | 4-Stroke | 1998 | 823547A2 | Fits 1F50452UD, 1F50452UN |
| Force | 40 | 40 | 2-Stroke | 1995–1997 | 823547A2 | Fits 0E093700 THRU 0E138599, H040312RD, H040312RR, H040312RX, H040412RD, 0E138600 THRU 0E202999, H040312SD, H040312ST, H040412SD, H040412ST, 0E203000 THRU 0E287999, H040312TD, H040312TT, H040412TD, H040412TL, H040412TT |
| Force | 50 | 50 | 2-Stroke | 1995–1997 | 823547A2 | Fits 0E093700 THRU 0E138599, H050312RD, H050312RR, H050312RX, H050412RD, 0E138600 THRU 0E202999, H050312SD, H050412SD, H050412ST, 0E203000 THRU 0E287999, H050312TD, H050412TD, H050412TT |
| Mariner | 30 | 30 | 2-Stroke | 1995–1999 | 823547A2 | Multiple model variants including EHO, ELHO, ELO, ELPTO, EO |
| Mariner | 40 | 40 | 2-Stroke | 1995–1999 | 823547A2 | Multiple model variants including ELO, ELPT, ELPTO, EO |
| Mariner | 40 ELPT | 40 | 4-Stroke | 1998 | 823547A2 | Fits 7F41412GF |
| Mariner | 45 ELPT | 45 | 4-Stroke | 1996–1997 | 823547A2 | Fits 7F45412EF, 7F45412FF |
| Mariner | 50 EL | 50 | 4-Stroke | 1998 | 823547A2 | Fits 7F50352GD |
| Mariner | 50 ELHPT | 50 | 4-Stroke | 1996–1998 | 823547A2 | Fits 7F50411ED, 7F50411FD, 7F50411GD |
| Mariner | 50 ELPT | 50 | 4-Stroke | 1995–1998 | 823547A2 | Fits 7F50412DD, 7F50412ED, 7F50412FD, 7F50452FD, 7F50412GD |
| Mariner | 50 ELPT/BF | 50 | 4-Stroke | 1998 | 823547A2 | Fits 7F50452GD |
Technical Specs
- Product Type
- Gearcase Seal Kit
- Installation
- OEM replacement for lower unit gear housing
- Housing Material
- Rubber/Plastic
- Dimensions
- 17.0" L x 12.0" W x 3.0" H
- Weight
- 0.30 kg (0.66 lb)
- Other Technical Attributes
- For use with Mercury/Mariner/Force lower unit gear housing assemblies
What’s in the Box
- 1 x Gear Housing Seal Kit
Installation Notes
- Always consult your engine's official service manual before beginning work.
- Disconnect the negative battery cable to prevent accidental starting.
- Position a drain pan under the lower unit and remove the gear lube drain/fill screws to empty the old oil.
- Remove the bolts securing the lower unit (gearcase) to the outboard's driveshaft housing and carefully lower it.
- Following your manual, disassemble the gear housing to access the old seals (propshaft seals, driveshaft seals, etc.).
- Carefully remove all old seals and O-rings, taking care not to scratch the housing surfaces.
- Thoroughly clean all sealing surfaces of any old adhesive, corrosion, or debris.
- Lightly lubricate the new seals with marine grease and press them into place using a proper seal driver or socket. Ensure they are seated correctly and evenly.
- Reassemble the gear housing components according to the manual, torquing all bolts to specification.
- Reinstall the lower unit onto the outboard, using a new gasket if required.
- Refill the gearcase with the manufacturer-recommended marine gear lubricant to the proper level. Reinstall and tighten drain/fill screws with new gaskets.
- Reconnect the battery, start the engine, and check for any leaks around the lower unit.
Troubleshooting & FAQ
How do I know if this seal kit is the right one for my motor?
This kit is designed for specific HP ranges and years. To ensure a perfect match, please consult the detailed compatibility tables on this page. For Mercury engines, it's crucial to also check your engine's serial number against the notes provided.
What are the symptoms of a bad gearcase seal?
The most common sign is "milky" or creamy-looking gear lube, which indicates water has mixed with the oil. You might also notice gear oil leaking from the propeller shaft area or a persistent burning oil smell.
How often should lower unit seals be replaced?
Lower unit seals should be inspected during regular service intervals (typically every 100 hours or annually). It is recommended to replace them as a preventative measure every 200-300 hours of operation, or immediately if any leaks or water intrusion are detected.
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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