Drain Screw Gasket – Fits Mercury/MerCruiser & Johnson/Evinrude (Replaces 12-19183, 307552)

$12.49 $19.00

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Drain Screw Gasket – Fits Mercury/MerCruiser & Johnson/Evinrude (Replaces 12-19183, 307552) is backordered and will ship as soon as it is back in stock.

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This aftermarket Drain Screw Gasket – Fits Mercury/MerCruiser & Johnson/Evinrude Lower Units (Replaces 12-19183, 307552) is designed for a perfect seal on lower units with 3/8-16 drain and fill screw holes. It is broadly compatible with all Mercury and MerCruiser outboards and stern drives (excluding Japanese-origin models), as well as all Johnson/Evinrude and Chrysler/Force/US Marine outboard lower units requiring the same size gasket.

It serves as a direct interchange for numerous OEM and aftermarket part numbers, including the Mercury 12-19183 series, Johnson/Evinrude 307552, Sierra 18-2244, GLM 31170, and Mallory 9-60101.

Engineered to create a tear-resistant seal without requiring over-tightening or compression.
Constructed from durable rubber-coated stainless steel for longevity and reliable sealing.
It is highly recommended to replace the gasket with every gearcase oil change to prevent leaks.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket brands.

Brand	Part Number
Mercury	12-19183 / 12-19183Q02 / 12-19183K02 / 12-191833 / 191832 / 19183 / 19183B / 20260B / 20260
Johnson/Evinrude	307552 / 300434
Chrysler/Force/US Marine	F50556 / F8077 / F8186
Sierra	18-2244 / 18-2945 / 18-29451-9
GLM	31170
Mallory	9-60101 / 9-60102
SEI Marine	98-102-09

Engine & Model Compatibility

Confirm your engine model and year in the table below to ensure accurate fitment.

Mercury/MerCruiser: Fits all outboards and stern drives with 3/8-16 drain/fill screw holes, with the exception of models of Japanese origin.

Johnson/Evinrude: Compatible with all outboard lower units that use a 3/8-16 drain/fill screw.

Chrysler/Force/US Marine: Fits all outboard lower units equipped with 3/8-16 drain/fill screw holes.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	Outboard Motors	All	2-Stroke & 4-Stroke	All	12-19183	Except Japanese origin models
Mercury	Outboard Lower Units	All	2-Stroke & 4-Stroke	All	12-19183	For 3/8-16 drain/fill screw holes
MerCruiser	All Stern Drives	All	N/A	All	12-19183	For 3/8-16 drain/fill screw holes
MerCruiser	4.3L, 5.0L, 5.7L, 6.2L	All	N/A	All	12-19183	Confirmed fit
MerCruiser	350, 377, 383 MPI	All	N/A	All	12-19183	Confirmed fit
Johnson/Evinrude	Outboard Lower Units	All	2-Stroke & 4-Stroke	All	307552	For 3/8-16 drain/fill screw holes
Johnson/Evinrude	Multiple Models	18-75 HP	2-Stroke & 4-Stroke	All	307552	Used with compatible drain screws
Chrysler/Force/US Marine	Outboard Lower Units	All	2-Stroke & 4-Stroke	All	F50556, F8077, F8186	For 3/8-16 drain/fill screw holes

Technical Specs

Product Type: Drain/Fill Screw Gasket
Installation: Use with 3/8-16 drain/fill screw holes
Housing Material: Rubber-coated stainless steel
Housing Color: Yellow (newer design) or Blue (older design)
Fitting Type: Washer/Gasket
Thread Size: 3/8-16
Other Technical Attributes: Designed to form tear-resistant seal without requiring compression

What’s in the Box

1 x Drain Screw Gasket (Replaces 12-19183Q02)

Installation Notes

Position a suitable drain pan under the lower unit's drain screw.
Carefully remove the drain/fill screw, allowing the old gearcase oil to drain completely.
Remove and discard the old drain screw gasket.
Clean the screw and the sealing surface on the lower unit to remove any old residue or debris.
Place the new gasket onto the drain screw.
Reinstall the screw and tighten it to the manufacturer's specified torque. Do not overtighten.
Refill the lower unit with the correct type and amount of gear lube through the fill port.
Install the fill port screw with its new gasket, and check both for leaks.

Troubleshooting & FAQ

How often should I replace this gasket?

For a leak-free seal, it is best practice to replace the drain screw gasket every time you change the gearcase oil. Reusing an old gasket increases the risk of oil or water leaks.

What is the difference between the yellow and blue gaskets?

The color indicates the design generation—yellow is newer, and blue is older. However, both are functionally identical, made from the same materials to the same specifications, and are completely interchangeable.

Will this gasket fit a Japanese-made Mercury outboard?

No. This gasket is specifically designed for Mercury and MerCruiser models that are not of Japanese origin. Please verify your engine's model and origin before purchasing.

What are the signs of a failing gasket?

A failing gasket will typically cause a gear lube leak around the drain screw. You may also notice a milky or watery appearance in your gear oil during a change, which indicates water intrusion from a bad seal.

Is an OEM part better than this aftermarket gasket?

This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials and performance. Each part is manufactured in an ISO 9002 certified facility and is batch-inspected to ensure quality and consistency.

What are your shipping speeds and costs?

We ship worldwide quickly—typical transit is 5–15 days for most regions. Standard shipping is free, and expedited options will appear at checkout if they are available for your location.

What is the warranty and return policy?

This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their original condition. See our policy page or reach out for instructions.

Safety & Important Info

Verify images and specifications against your original part before ordering. If anything differs—even if your model appears on a compatibility list—do not purchase.
This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
Professional installation is recommended for safety and to ensure optimal performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for demanding real-world conditions.
Fast Global Fulfillment — We offer free standard delivery to most regions with an average transit time of 5–15 days.
Manufacturer-Direct Value — By working directly with our manufacturing partners, we provide fair pricing without compromising on materials or quality control.

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