Carburetor Adaptor to Manifold Gasket – Fits Mercury MerCruiser V8 Engines (Replaces 27-70142)

$2.49 $3.00

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Product Details

This aftermarket Carburetor Adaptor to Manifold Gasket creates a reliable seal between the carburetor adaptor and intake manifold. It is designed specifically for Mercury MerCruiser V8 engines, including Ford 302 (1971–1977) and Ford 351 (1975–1977) applications.

It serves as a direct replacement for several part numbers, including Mercury 27-70142, Sierra 18-0360, Mallory 9-61008, GLM 32140, Barr MC47-27-70142, and Holley 700-32140.

Installs between the carburetor adaptor and intake manifold.
Designed for use with gasoline fuel systems.
Includes one adaptor-to-manifold gasket.

Part Number Matrix

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

Brand	Part Number
Mercury	27-70142
Sierra	18-0360
Mallory	9-61008
GLM	32140
Barr	MC47-27-70142
Holley	700-32140

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For MerCruiser applications, verify your engine's model and serial number range to ensure correct fitment.

Brand	Model	Stroke	Years	OEM Part No.	Notes
MerCruiser	888 (2 BBL.) FORD 302 V-8	4-Stroke	1971–1977	27-70142	Serial #3108723 and up
MerCruiser	233 FORD 351 V-8	4-Stroke	1975–1977	27-70142	Serial #4173000 through #4902304
MerCruiser	233 MIE FORD 351 V-8	4-Stroke	1975–1976	27-70142	Serial #4173000 through #4775784

Technical Specs

Product Type: Carburetor Adaptor Gasket
Installation: Between carburetor adaptor and intake manifold
Fuel Type: Gasoline
Dimensions: 17.0" L x 12.0" W x 0.5" H
OEM Part Number: 27-70142
Manufacturer: Mercury Marine / MerCruiser

What’s in the Box

1x Gasket, Adaptor to Manifold (27-70142)

Installation Notes

Ensure the engine is completely cool and disconnect the battery terminals for safety.
Remove the carburetor and carburetor adaptor assembly from the intake manifold.
Carefully remove the old gasket and thoroughly clean any residual material from both the manifold and adaptor surfaces.
Position the new gasket onto the intake manifold, ensuring all mounting holes are properly aligned.
Reinstall the carburetor adaptor and tighten the mounting bolts to the manufacturer's specified torque sequence and values.
Reconnect the battery, start the engine, and carefully inspect for any vacuum or fuel leaks around the seal.

Troubleshooting & FAQ

How do I know if this gasket fits my engine?

This gasket is for specific MerCruiser V8 engines, including Ford 302 (1971–1977) and 351 (1975–1977) models. Always verify your engine model and serial number against the compatibility table. Cross-referencing your old part number with the interchange list also helps confirm fitment.

What are the signs of a failed carburetor adaptor gasket?

Common symptoms include vacuum leaks (causing a rough or high idle, stalling, and poor acceleration), reduced engine performance, and sometimes a whistling sound from the engine bay at idle.

Can I reuse my old gasket?

No. Gaskets provide a seal by conforming to surface irregularities under pressure. Once compressed, they lose their ability to create another reliable seal. Always use a new gasket during installation to prevent critical vacuum or fuel leaks.

Is any sealant required with this gasket?

Generally, this type of gasket is designed to be installed dry. However, always consult your engine's official service manual for specific recommendations regarding the use of sealants for your application.

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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