Gasket – Fits Mercury-Mercruiser Inboard/Outboard Engines (Replaces Mercury-Mercruiser 27-64692)

$3.75

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Product Details

This replacement Gasket – Fits Mercury-Mercruiser Inboard/Outboard Engines and is designed for a wide range of carbureted 4-cylinder and 6-cylinder models. It creates a critical seal for the carburetor base, preventing performance-robbing vacuum leaks and potential fuel leaks.

This part offers a direct interchange for Sierra 18-0356 and Mercury-Mercruiser 27-64692.

Installation Location: Mounts between the carburetor and the intake manifold.
Common Application: Fits various Mercury-Mercruiser engines using Rochester 2-barrel (2G) carburetors.

Part Number Matrix

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

Brand	Part Number
Sierra	18-0356
Mercury-Mercruiser	27-64692

Engine & Model Compatibility

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

This gasket is known to fit the following Mercury-Mercruiser engines. Verifying your engine's original carburetor number against the notes can further guarantee compatibility.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercruiser	90 L4	90	4-Stroke	1970–1972	27-64692	Original Carb #1351-4263A1/A2, MFG Model #7040082/7041369 R 2/2G C
Mercruiser	110 L4	110	4-Stroke	1963–1966	27-64692	Original Carb #1336-2076, MFG Model #7036543 R 2/2G C
Mercruiser	120 L4	120	4-Stroke	1964–1986	27-64692	Original Carb #1336-2076 / #1336-3594A1 / #1351-4263A3 / #1351-5202A1 / #1351-6065A2 / #1351-7354A1 / #1351-8480A2, various MFG Models
Mercruiser	2.5L L4	2.5	4-Stroke	1987–1989	27-64692	Original Carb #1351-8480A2
Mercruiser	140 L4	140	4-Stroke	1968–1986	27-64692	Original Carb #1351-3635A1 / #1351-4032A1 / #1351-4293A1 / #1351-5203A1 / #1351-7355A1 / #1351-8480A2, various MFG Models
Mercruiser	3.0L L4	3.0	4-Stroke	1987–1989	27-64692	Original Carb #1351-8480A2
Mercruiser	470 L4	470	4-Stroke	1976–1984	27-64692	Original Carb #1376-5990A1, MFG Model #17057132 R/2G C
Mercruiser	485 L4	485	4-Stroke	1980–1982	27-64692	Original Carb #1376-5990A1, MFG Model #17057132 R 2/G C
Mercruiser	150 L6	150	4-Stroke	1964–1966	27-64692	Original Carb #1338-2633, MFG Model #7025188 R 2/2G C
Mercruiser	160 L6	160	4-Stroke	1967–1969	27-64692	Original Carb #1338-2991 / #1351-3635A1, MFG Model #7026088 / #7036646 R 2/2G C
Mercruiser	165 (6-Cyl.) L6	165	4-Stroke	1970–1981	27-64692	Original Carb #1351-4282A1 / #1351-4871A1 / #1351-5204A1 / #1351-7356A1, various MFG Models

Technical Specs

Product Type: Gasket
Installation: Carburetor Base
Dimensions: Length: 393.7 mm (15.5 in) x Width: 304.8 mm (12.0 in) x Height: 5.08 mm (0.2 in)
Weight: 0.02 kg (0.05 lbs)
Manufacturer Part Number: 64692
GTIN: 0745061166936

What’s in the Box

1 x Gasket (27-64692)

Installation Notes

Ensure the engine is off and the battery is disconnected. Shut off the fuel supply.
Remove the flame arrestor, fuel line, and any throttle or choke linkages from the carburetor.
Carefully unbolt and remove the carburetor from the intake manifold.
Remove the old gasket. Thoroughly clean both mating surfaces, ensuring they are free of old gasket material, sealant, and debris.
Position the new gasket onto the intake manifold, aligning it with the mounting studs or bolt holes.
Carefully place the carburetor onto the new gasket.
Tighten the mounting bolts or nuts in a crisscross pattern to the torque specified in your engine's service manual. Do not overtighten.
Reconnect the fuel line and all linkages.
Reinstall the flame arrestor, turn the fuel supply on, and reconnect the battery.
Start the engine and carefully inspect for any fuel or vacuum leaks around the carburetor base.

Troubleshooting & FAQ

How do I confirm this gasket fits my engine?

This gasket is specifically for certain Mercury-Mercruiser 4-cylinder and 6-cylinder engines, typically those with Rochester 2-barrel carburetors. The best way to confirm is by checking your engine model and year against our "Engine & Model Compatibility" list. For absolute certainty, matching the OEM part number (27-64692) or the Sierra cross-reference (18-0356) is recommended.

What are the signs of a bad carburetor base gasket?

A failing gasket typically causes a vacuum leak, leading to symptoms like a rough or high idle, engine stalling, hesitation on acceleration, and poor fuel economy. You might also hear a hissing or whistling sound from the engine bay.

Do I need to use sealant with this gasket?

No, this gasket is typically designed to be installed dry. The gasket material itself is made to create a seal. Adding chemical sealants can sometimes interfere with its function or cause it to squeeze out of place. Always follow your engine's service manual for specific instructions.

How often should this gasket be replaced?

There isn't a fixed service interval. The gasket should be replaced any time the carburetor is removed for service or if symptoms of a leak are detected.

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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