Face Plate to Water Pump Gasket – Fits Mercury/Mercruiser Outboards 20 HP (Replaces 27-396231)

$2.44 $3.00

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Product Details

This is a replacement Face Plate to Water Pump Gasket – Fits Mercury/Mercruiser Outboards 20 HP (Replaces 27-396231), specifically for vintage 2-stroke models such as the Merc 200 series. It creates a crucial seal between the water pump housing and the face plate to prevent coolant leaks and ensure efficient engine cooling.

This component directly replaces Mercury/Mercruiser OEM part numbers 27-39623 and 27-396231.

Installs mechanically between the water pump and face plate.
Engineered from durable gasket material for a reliable seal.
Essential for routine water pump service and maintenance.

Part Number Matrix

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

Brand	Part Number	Notes
Mercury/Mercruiser	27-396231	Current part number
Mercury/Mercruiser	27-39623	Superseded by 27-396231

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mercruiser engines, this gasket is primarily intended for specific vintage 20 HP models. Please verify your part number visually and against our compatibility list.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	Merc 200	20	2-Stroke	Vintage models	27-396231	Previously 27-39623

Technical Specs

Product Type: Face Plate to Water Pump Gasket
Installation: Mechanical installation between face plate and water pump
Housing Material: Gasket material
Product Dimensions: 6.0 in × 7.5 in × 1.06 in
Weight: 0.02 lbs (0.009 kg)

What’s in the Box

1 x Face Plate To Water Pump Gasket (27-396231)

Installation Notes

Disconnect the battery and ensure the engine has completely cooled.
If necessary, drain the cooling system to access the water pump assembly without spillage.
Carefully unbolt and remove the water pump face plate.
Remove the old gasket, taking care not to damage the mating surfaces.
Thoroughly clean both the pump housing and the face plate surfaces, removing any old gasket residue.
Position the new gasket correctly, aligning it with the bolt holes.
Reinstall the face plate and tighten the bolts in a crisscross pattern to the manufacturer's specified torque.
Refill the cooling system, start the engine, and carefully inspect for any leaks around the housing.

Troubleshooting & FAQ

How do I know if this gasket fits my engine?

This gasket is designed for vintage Mercury/Mercruiser 20 HP 2-stroke outboards, including the Merc 200 series. The most reliable method is to check if your old part number is 27-39623 or 27-396231. Always compare your old gasket to the images provided to ensure an exact match in shape and size.

What are the signs of a failing water pump gasket?

Common signs include visible water leaks around the water pump housing, engine overheating alarms, steam from the engine cowling, or a weak or intermittent water stream from the "telltale" outlet.

What is the difference between part numbers 27-39623 and 27-396231?

The part number 27-396231 is the official replacement that supersedes the older 27-39623. They are functionally identical, with 27-396231 being the current production part for this application.

Should I use sealant with this gasket?

This gasket is designed to be installed dry on clean, smooth surfaces. Applying gasket sealant is generally not required or recommended, as excess can squeeze into cooling passages and cause blockages. Always refer to your engine's official service manual for specific instructions.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

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