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FLASHSALE26

Lower Unit Oil Drain Plug Gasket – For Yamaha, Mercury & Mariner Outboards

Regular price $12.65

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Product Details

This is an aftermarket lower unit oil drain plug gasket for selected Yamaha, Mercury and Mariner outboard applications. It is used with the lower-unit oil drain or fill plug to help seal the gearcase during service and reduce the risk of oil leakage or water intrusion.

The company product record identifies this as a single gasket, not a complete drain-plug assembly or a multi-piece service kit. The gasket is listed under the following manufacturer and aftermarket references. Always verify the exact part number and engine application before installation.

  • Single replacement gasket for lower-unit oil drain or fill plug service.
  • Applicable brand references include Yamaha Outboard, Mercury and Mariner.
  • Replace the gasket whenever the corresponding drain or fill plug is removed.
  • Aftermarket replacement; the plug itself is not included.

Part Number References

These references are provided for identification and cross-reference purposes. They should not be treated as confirmation for every engine model.

Brand or source Reference Description
Yamaha 90430-08020 Manufacturer reference listed for the gasket
Yamaha 90430-08003 Manufacturer reference listed for the gasket
Mercury 27-95220 Manufacturer reference listed for the gasket
Mercury 27-81987 Manufacturer reference listed for the gasket
Sierra 18-4698 Aftermarket cross-reference
Mallory Marine 9-60100 Aftermarket cross-reference

Documented Application Examples

Catalog records associate the listed references with multiple engine applications, including the examples below. Model, year, stroke and serial conditions must remain together when checking fitment; an OEM number alone is not sufficient confirmation.

Brand Model or application Horsepower Stroke Year or serial condition Reference
Yamaha 115ETLN / 115ETXN 115 2-Stroke 1984 90430-08020-00
Yamaha 15ELN, 15ESK, 15ESN, 15LK, 15LN, 15SK and 15SN 15 2-Stroke 1984 90430-08020-00
Yamaha F115JB / F115LB / F115XB 115 4-Stroke 2016 90430-08003-00
Yamaha F150JB / F150LB / F150XB 150 4-Stroke 2016 90430-08003-00
Mercury 225 EFI 225 4-Stroke Serial 0T653945 and up 27-81987
Mercury 2, 2.5 and 3.3 horsepower gear-housing applications 2–3.3 Varies by catalog application Specific serial ranges apply 27-95220

Important: The examples above are not a universal-fit statement. Compare your original gasket and reference number, then confirm the complete engine model, year, stroke and serial-number range in the applicable service or parts catalog.

Specifications

Product type
Lower unit oil drain plug gasket
Quantity
1 gasket
Application
Lower-unit oil drain or fill plug sealing
Brand applications
Yamaha Outboard, Mercury and Mariner applications as identified by the listed references
Product status
Aftermarket replacement; not an OEM-branded component

What’s in the Box

  • 1 × Lower unit oil drain plug gasket

The drain plug, fill plug, gear oil and other service parts are not included.

Installation Notes

Use the installation procedure and torque specification supplied by your engine manufacturer for your exact model and serial range.

  1. Place the engine in a safe, stable position and clean the area around the lower-unit plug.
  2. Remove the plug and discard the used gasket. Inspect the plug and sealing surface for damage, corrosion or debris.
  3. Install the new gasket in the same sealing position as the original.
  4. Reinstall the plug and tighten it to the manufacturer’s specified torque. Do not overtighten or reuse a damaged gasket.
  5. After servicing, check for leaks and confirm the lower-unit oil level according to the engine service procedure.

Maintenance and FAQ

Should the gasket be replaced every time the plug is removed?

Yes. A new gasket is recommended whenever the corresponding lower-unit drain or fill plug is removed. Reusing a compressed or damaged gasket can increase the risk of leakage.

Does this product include the drain plug?

No. This listing is for one replacement gasket only. The drain or fill plug is not included.

Will this gasket fit every Yamaha, Mercury or Mariner outboard?

No universal-fit claim is made. The listed references are associated with multiple applications, but fitment depends on the complete engine model, year, stroke and serial-number range. Confirm the reference against your original part and the applicable catalog before ordering.

Is this an OEM gasket?

No. This is an aftermarket replacement referenced to the manufacturer and aftermarket numbers shown above. Brand names and part numbers are used only to identify application references.

Safety and Fitment Information

  • Verify the part number, plug style and sealing surface before installation.
  • Keep model, year, horsepower, stroke and serial-number conditions together when checking fitment.
  • Use the manufacturer’s service instructions and torque specification for your exact engine.
  • Do not operate the engine if the lower unit shows an oil leak or if water contamination is suspected.

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