Mercury Gearcase Seal Kit – Fits Mercury/Mariner 75-225 HP Outboards (Replaces 26-55682A1)
Mercury Gearcase Seal Kit – Fits Mercury/Mariner 75-225 HP Outboards (Replaces 26-55682A1) 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
Mercury Gearcase Seal Kit – Fits Mercury/Mariner 75-225 HP Outboard...
Product Details
This aftermarket Mercury Gearcase Seal Kit provides all the necessary seals, gaskets, and O-rings to service the lower unit on a wide range of Mercury and Mariner 75-225 HP outboard engines. It is designed for inline 4-cylinder and V6 models, primarily from the late 1970s through the early 1990s.
This kit serves as a direct replacement for Mercury Marine 26-55682A1 and is an interchange for Sierra 18-2653, GLM 87520, and Mallory 9-74203.
- Includes a complete set of components for a lower gearcase reseal.
- Professional installation is recommended for optimal performance and safety.
- Total kit weight is approximately 0.25 lbs (0.11 kg).
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Mercury Marine | 26-55682A1 |
| Sierra | 18-2653 |
| GLM | 87520 |
| Mallory | 9-74203 |
Engine & Model Compatibility
Confirm your engine model and serial number in the table below to ensure accurate fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury/Mariner | 75 (4 CYL.) | 75 | 2-Stroke | 6432901 & Up | 26-55682A1 | |
| Mercury/Mariner | 75 (4 CYL.) | 75 | 2-Stroke | 7208573 & Up | 26-55682A1 | |
| Mercury/Mariner | 75 (4 CYL.) | 75 | 2-Stroke | 9393856 & Up | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 4831999–5582561 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 5582562–6432900 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 7110998–7146212 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 7146213–7208572 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 8050200–8067014 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 8067015 & Up | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 9177626–9256130 | 26-55682A1 | |
| Mercury/Mariner | 800 (4 CYL.), 80 (4 CYL.) | 80 | 2-Stroke | 9256131–9393855 | 26-55682A1 | |
| Mercury/Mariner | 90 (6 CYL.) | 90 | 2-Stroke | 5594657–6436122 | 26-55682A1 | |
| Mercury/Mariner | 90 (6 CYL.) | 90 | 2-Stroke | 6436123 & Up | 26-55682A1 | |
| Mercury/Mariner | 90 (6 CYL.) | 90 | 2-Stroke | 7147088–7208847 | 26-55682A1 | |
| Mercury/Mariner | 90 (6 CYL.) | 90 | 2-Stroke | 7208848 & Up | 26-55682A1 | |
| Mercury/Mariner | 90 (6 CYL.) | 90 | 2-Stroke | 8071020 & Up | 26-55682A1 | |
| Mercury/Mariner | 900, 90 | 90 | 2-Stroke | 4845301–5299505 | 26-55682A1 | |
| Mercury/Mariner | 900, 90 | 90 | 2-Stroke | 7111698–7123762 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 5314656–5600966 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 5600967–6436122 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 6436123 & Up | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 7131213–7147987 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 7147988–7208847 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 7208848 & Up | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 8061120–8061269 | 26-55682A1 | |
| Mercury/Mariner | 115 (6 CYL.) | 115 | 2-Stroke | 8067340 & Up | 26-55682A1 | |
| Mercury/Mariner | 1150, 115 | 115 | 2-Stroke | 4855153–5314655 | 26-55682A1 | |
| Mercury/Mariner | 1150, 115 | 115 | 2-Stroke | 7112248–7131212 | 26-55682A1 | |
| Mercury/Mariner | 1150, 115 | 115 | 2-Stroke | 8051950–8061119 | 26-55682A1 | |
| Mercury/Mariner | 140 | 140 | 2-Stroke | 5625108 & Up | 26-55682A1 | |
| Mercury/Mariner | 140 | 140 | 2-Stroke | 7150413 & Up | 26-55682A1 | |
| Mercury/Mariner | 140 | 140 | 2-Stroke | 8066065 & Up | 26-55682A1 | |
| Mercury/Mariner | 1400, 140 | 140 | 2-Stroke | 4865678–5327662 | 26-55682A1 | |
| Mercury/Mariner | 1400, 140 | 140 | 2-Stroke | 7112773–7132512 | 26-55682A1 | |
| Mercury/Mariner | 1400, 140 | 140 | 2-Stroke | 8052650–8052879 | 26-55682A1 | |
| Mercury/Mariner | V-150 | 150 | 2-Stroke | 4868998–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-150 | 150 | 2-Stroke | 5600162–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-150 Magnum | 150 | 2-Stroke | 5600162–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-150 Marathon | 150 | 2-Stroke | 5600162–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-150 Work | 150 | 2-Stroke | 4868998–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-1500 | 150 | 2-Stroke | 4868998–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-1500 | 150 | 2-Stroke | 5600162–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-150-XR-2 | 150 | 2-Stroke | 4868998–0A904645 | 26-55682A1 | |
| Mercury/Mariner | V-175 | 175 | 2-Stroke | 4301235–0C100860 | 26-55682A1 | |
| Mercury/Mariner | V-175 | 175 | 2-Stroke | 8058870 & Up | 26-55682A1 | |
| Mercury/Mariner | V-200 | 200 | 2-Stroke | 5624878–0C100860 | 26-55682A1 | |
| Mercury/Mariner | V-225 | 225 | 2-Stroke | 5628028 & Up | 26-55682A1 |
Technical Specs
- Product Type
- Gearcase/Lower Unit Seal Kit
- Installation
- Professional recommended
- Dimensions
- 17.0" L x 11.5" W x 4.0" H
- Weight
- 0.25 lbs (0.11 kg)
- Kit Contents
- Complete seal kit for lower gearcase service
What’s in the Box
- 2 x Oil Seal (18-2002)
- 1 x Oil Seal (18-2007)
- 1 x Oil Seal (18-2009)
- 1 x Oil Seal (18-2013)
- 1 x Oil Seal (18-2014)
- 1 x Oil Seal (18-2048)
- 1 x Oil Seal (18-2050)
- 1 x Oil Seal (18-2053)
- 1 x Water Pump Gasket (18-2801)
- 1 x Water Pump Base Gasket (18-2826)
- 1 x Water Pump Gasket (18-2914)
- 1 x Water Pump Gasket (18-2915)
- 2 x Drain Screw Gasket (18-2945)
- 1 x Rubber Washer (18-2948)
- 1 x Water Pump Housing Bushing (18-3110)
- 1 x O-Ring (18-7153)
- 1 x O-Ring (18-7157)
- 1 x O-Ring (18-7158)
- 1 x O-Ring (18-7159)
- 1 x O-Ring (18-7161)
- 1 x O-Ring (18-7162)
- 1 x O-Ring (18-7173)
- 1 x O-Ring (18-7426)
Installation Notes
- Disconnect the battery and remove the spark plug leads for safety.
- Drain the gearcase lubricant completely into an appropriate container.
- Remove the propeller assembly.
- Unbolt and carefully lower the gearcase from the outboard's midsection.
- Disassemble the gearcase as required to access the seals, taking photos or notes for reassembly.
- Carefully remove all old seals, O-rings, and gaskets, avoiding damage to housing surfaces.
- Thoroughly clean all sealing surfaces to ensure they are free of old material and corrosion.
- Install the new seals and components from the kit, lightly lubricating them with appropriate marine grease.
- Reassemble the gearcase according to the manufacturer's service manual specifications and torque values.
- Reinstall the lower unit, refill with fresh gear lube to the correct level, and check for any leaks before operation.
Troubleshooting & FAQ
How do I confirm this kit fits my specific engine?
This kit fits a wide range of Mercury/Mariner outboards. The most accurate way to confirm fitment is by matching your engine's model and serial number to the ranges listed in the Engine & Model Compatibility table. OEM data often relies on serial numbers rather than exact years for precision.
What are common signs that my gearcase seals need replacement?
The most common indicators of failing gearcase seals include visible oil leaking from the lower unit (especially around the propeller shaft), or finding milky, emulsified gear lube during a fluid check, which signifies water intrusion.
Is this kit sufficient for a complete lower unit reseal?
Yes, this is a comprehensive kit containing the necessary seals, gaskets, and O-rings for a standard lower unit service on compatible models. Please review the "What's in the Box" section for a full list of included components.
Why does the compatibility table use serial numbers instead of model years?
Manufacturers like Mercury often make mid-year production changes. Using serial number ranges is the most reliable method to ensure you get the correct parts that correspond to your specific engine build, overcoming variations that may exist within the same model year.
Is this an OEM part or an aftermarket replacement?
This listing is for a high-quality aftermarket replacement part, not an OEM component. It is engineered to meet or exceed OEM specifications using comparable materials and is manufactured in an ISO 9002 certified facility with rigorous batch inspections.
What are the shipping costs and delivery times?
We offer fast worldwide shipping, with typical transit times of 5–15 days for most regions. Standard shipping is free for all orders, and expedited options may be available at checkout depending on your location.
What is the warranty and return policy for this part?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard return window for unused items in their original condition. Please see our full policy page or reach out for instructions.
Safety & Important Info
- Verify images and specifications against your original part before purchasing. If anything differs—even if your model appears compatible—do not order.
- This is an aftermarket replacement part, not an original equipment manufacturer (OEM) component.
- Professional installation is strongly recommended for safety, proper function, and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world reliability.
- Fast Global Fulfillment — We provide free standard delivery to most regions worldwide, with typical transit times of 5–15 days.
- Manufacturer-Direct Value — By working directly with manufacturers, we offer fair pricing without compromising on materials or quality control.
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