Gearcase Drain Plug Seal – Fits Mercury/Mariner/MerCruiser Applications (Replaces 26-830749, 8M0204693)
Gearcase Drain Plug Seal – Fits Mercury/Mariner/MerCruiser Applications (Replaces 26-830749, 8M0204693) is backordered and will ship as soon as it is back in stock.
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Gearcase Drain Plug Seal – Fits Mercury/Mariner/MerCruiser Applicat...
Gearcase Drain Plug Seal – Fits Mercury/Mariner/MerCruiser Applications (Replaces 26-830749, 8M0204693) is backordered and will ship as soon as it is back in stock.
Product Details
This Gearcase Drain Plug Seal is a washer-style replacement seal for compatible Mercury, Mariner, and MerCruiser gearcase drain and fill plugs. It is intended to help seal the plug-to-housing interface during gearcase service and reduce the risk of lubricant leakage or water entering through the plug opening.
This listing references Mercury part numbers 26-830749 and 8M0204693. Always compare the part number, plug design, and dimensions with the seal being replaced before installation.
- Washer-style seal for compatible gearcase drain and fill plugs.
- Useful during routine lower-unit gear lubricant changes.
- Install a new seal whenever the applicable plug is removed, when recommended by the engine or sterndrive manufacturer.
Part Number References
The following numbers are reference points for identifying the intended replacement application. Verify the number against your engine or sterndrive documentation before ordering.
| Brand | Part Number |
|---|---|
| Mercury | 26-830749 |
| Mercury | 8M0204693 |
| Sierra | 18-2244 |
Compatibility Information
This seal is described for compatible Mercury and Mariner outboard gearcases and MerCruiser sterndrive applications that use the referenced plug and seal arrangement. Compatibility cannot be confirmed by brand or horsepower alone because model, year, serial range, plug design, and application may vary.
| Brand | Application | Reference | Fitment Notes |
|---|---|---|---|
| Mercury / Mariner | Compatible outboard gearcases | 26-830749; 8M0204693 | Confirm the original seal and plug arrangement before purchase. |
| MerCruiser | Compatible sterndrive gearcases | 26-830749; 8M0204693 | Verify the exact drive model and service documentation. |
Technical Specifications
- Product Type
- Gearcase drain plug seal / sealing washer
- Application
- Compatible lower-unit or sterndrive gearcase drain and fill plugs
- Installation
- Position on the applicable plug before reinstalling the plug.
- Reference Part Numbers
- Mercury 26-830749 and 8M0204693
- Material
- Seal material is application-specific; compare the replacement with the original part.
What's in the Box
- Gearcase drain plug seal, according to the selected product quantity.
Check the order quantity or pack-size selection before checkout. Do not assume that a single-unit listing includes multiple seals.
Installation Notes
- Place a suitable drain pan beneath the lower unit or sterndrive gearcase.
- Remove the upper vent plug and lower drain plug using the correct tool for the plug design.
- Allow the gear lubricant to drain completely and inspect it for water contamination or metal debris.
- Remove the old seal and clean the plug and sealing surfaces.
- Place the new seal on the applicable drain or fill plug.
- Reinstall the lower plug first and tighten it to the manufacturer's specified torque. Do not overtighten.
- Refill the gearcase with the manufacturer-recommended lubricant through the appropriate fill opening.
- Install the upper plug with its seal, tighten to the specified torque, and check both plugs for leaks.
Troubleshooting & FAQ
How do I confirm whether this seal fits my engine?
Compare the original seal and plug with the referenced part numbers, then verify the exact engine or sterndrive model, year, and serial range in the manufacturer's parts information. Brand or horsepower alone is not sufficient for confirmation.
When should the seal be replaced?
Replace the seal when it is removed, damaged, compressed, cracked, or no longer provides a reliable seal. Many service procedures recommend installing a new seal during gearcase lubricant changes.
What indicates a sealing problem?
Lubricant around the plug, continued leakage after tightening, or water contamination in the gear lubricant can indicate a damaged seal, damaged sealing surface, incorrect plug installation, or another gearcase problem.
Can I reuse the old seal?
Reuse is not recommended when the seal has been compressed, deformed, cracked, or contaminated. A new seal provides a better opportunity for a leak-free installation.
Is this an OEM part?
This listing is for a replacement seal identified by the referenced Mercury part numbers. Confirm the seller's brand and packaging details if an original manufacturer part is specifically required.
Does the listing include a drain plug?
No drain plug is described as included. The product is a replacement seal; verify the selected quantity and package contents before ordering.
Safety & Important Information
- Verify the exact part number, model, year, serial range, plug design, and dimensions before installation.
- Use the lubricant type and tightening torque specified by the engine or sterndrive manufacturer.
- Dispose of used gear lubricant according to local regulations.
- Stop and consult a qualified marine technician if the plug, threads, sealing surface, or gearcase shows damage.
About Sea Sierra
- Marine Replacement Parts — Parts are offered for maintenance and repair of compatible marine applications.
- Application Verification — Compare the product references with the original part and manufacturer's service information before ordering.
- Service-Focused Support — Use the exact engine or sterndrive details when requesting fitment assistance.
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