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FLASHSALE26

Lower Unit Drain Screw Gasket for Select Mercury and MerCruiser Applications – Replaces 12-19183-3, 12-19183K02 and 12-19183Q02

Regular price $18.50

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Product Details

This Lower Unit Drain Screw Gasket is an aftermarket replacement gasket for select Mercury Marine outboard and MerCruiser lower-unit applications. It is intended for use with drain or fill screws that specify the matching gasket and provides a replacement sealing surface during gear-lubricant service.

The gasket is documented as a replacement for Mercury Marine part number 12-19183-3. The product listing also references 12-19183K02 and 12-19183Q02 as replacement numbers. Because lower-unit hardware can vary by model, year and serial range, verify the part number and the original gasket before ordering.

  • Replacement gasket for compatible lower-unit drain or fill screws.
  • Helps restore the seal at the drain-screw interface during gear-lube service.
  • Sold as a 12-piece package for multiple service intervals or applications.

Part Number Matrix

Use the following references as a starting point for identification. Confirm the exact application with your engine or sterndrive documentation before installation.

Brand Part Number Role
Mercury Marine 12-19183-3 OEM reference
Mercury Marine 12-19183K02 Replacement reference
Mercury Marine 12-19183Q02 Replacement reference

Engine & Model Compatibility

Catalog references identify 12-19183-3 as a gasket used in Mercury lower-unit parts information and in MerCruiser lower-gearcase applications. Exact fitment depends on the engine or sterndrive model, year, serial range and the drain/fill screw configuration.

Brand Application Model, Year or Serial Conditions Reference Fitment Note
Mercury Select outboard lower units Not specified; verify by part number and hardware 12-19183-3 Do not assume universal fitment across all horsepower or stroke ranges.
MerCruiser Select lower-gearcase or stern-drive applications Not specified; verify by model and serial range 12-19183-3 Confirm the original gasket and drain-screw configuration before ordering.

Technical Specs

Product Type
Lower-unit drain screw gasket
Application
Compatible Mercury and MerCruiser drain or fill screw applications
Primary OEM Reference
12-19183-3
Additional Replacement References
12-19183K02 and 12-19183Q02
Package Quantity
12 gaskets
Installation
Install on a clean, compatible drain or fill screw during lower-unit service

What’s in the Box

  • 12 x Lower Unit Drain Screw Gasket

Installation Notes

  1. Place a suitable drain pan beneath the lower unit and follow the engine or sterndrive manufacturer’s service procedure.
  2. Remove the drain and vent or fill screws as directed for your specific application.
  3. Allow the gear lubricant to drain completely and inspect it for water or metal contamination.
  4. Clean the drain screw and the area around the threaded opening. Remove the old gasket.
  5. Inspect the screw threads and sealing surface. Do not reuse a damaged screw or a damaged sealing surface.
  6. Install one new gasket on the compatible drain or fill screw.
  7. Refill the lower unit with the manufacturer-specified lubricant using the procedure for your model.
  8. Reinstall the screws and tighten them to the manufacturer’s specified torque. Do not overtighten.
  9. Check for leaks after service and before operating the boat.

Troubleshooting & FAQ

How do I confirm that this gasket fits my engine?

Compare the OEM reference, the original gasket and the drain or fill screw with the references shown above. Model, year and serial-range fitment may vary, so do not rely on horsepower or brand alone.

Why should the gasket be replaced during gear-lube service?

A used gasket may be compressed, damaged or unable to seal correctly after removal. Installing a new compatible gasket helps restore the sealing surface and reduces the risk of lubricant leakage.

What are the signs of a sealing problem?

Inspect the drain or fill screw area for gear-lubricant seepage, drips or water contamination after service. Stop using the equipment and investigate any leak before further operation.

Does this listing include the drain screw?

No. This listing is for gaskets only. Drain screws, lubricant and other service parts are not included.

Is this an OEM part?

No. This is an aftermarket replacement gasket. Mercury and MerCruiser names and part numbers are used only to identify intended compatibility references.

Safety & Important Info

  • Verify the OEM reference, model, year, serial range and original hardware before ordering.
  • Do not assume this gasket fits every Mercury or MerCruiser model, horsepower rating or stroke configuration.
  • Use the manufacturer’s specified lubricant and screw torque for your application.
  • Professional installation is recommended when the correct fitment or service procedure is uncertain.

About Sea Sierra

  • Marine Replacement Parts — Practical aftermarket components for routine marine maintenance and repair.
  • Application-Focused Listings — Product references are provided to help you compare the part with your original component.
  • Service-Ready Packaging — This listing includes 12 replacement gaskets for compatible service applications.

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