Fuel Pump Mounting Gasket – Fits Mercury/MerCruiser 305/350 V8 Engines (Replaces 27-34898)

$5.59 $8.00

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Product Details

This aftermarket Fuel Pump Mounting Gasket provides a reliable seal between the fuel pump and engine block. It is designed for a wide range of Mercury/MerCruiser V6 and V8 engines (305, 350, 377, and 383 cubic inch models) manufactured between 1963 and 2002, ensuring proper fuel system function and preventing leaks.

It serves as a direct replacement for Mercury/Quicksilver 27-34898, Sierra 18-0876, and GLM 32750, offering a precise fit and OEM-equivalent performance.

Installs between the fuel pump and the engine block.
Engineered from durable paper/composite gasket material for gasoline applications.
Creates a secure seal to prevent fuel and oil leaks.

Part Number Matrix

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

Brand	Part Number
Mercury/Quicksilver	27-34898
Sierra	18-0876
GLM	32750

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This gasket fits numerous MerCruiser sterndrive and inboard engines. Please verify your specific model and year to ensure compatibility.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
MerCruiser	190 GM 283 V-8	190	4-Stroke	1963–1964	27-34898
MerCruiser	225 GM 327 V-8	225	4-Stroke	1963–1969	27-34898
MerCruiser	250 GM 327 V-8	250	4-Stroke	1968–1969	27-34898
MerCruiser	270 GM 350 V-8	270	4-Stroke	1969–1972	27-34898
MerCruiser	198 MIE (2 BBL.) GM 305 V-8	198	4-Stroke	1977	27-34898
MerCruiser	228 (4 BBL.) GM 305 V-8	228	4-Stroke	1977–1982	27-34898
MerCruiser	250 (2 BBL.) GM 350 V-8	250	4-Stroke	1977	27-34898
MerCruiser	260 (4 BBL.) GM 350 V-8	260	4-Stroke	1978–1987	27-34898
MerCruiser	230 (4 BBL.) GM 305 V-8	230	4-Stroke	1981–1987	27-34898
MerCruiser	5.0L (2 BBL.) GM 305 V-8	5.0L	4-Stroke	1988–1995	27-34898
MerCruiser	5.7L GM 350 V-8	5.7L	4-Stroke	1988–1997	27-34898
MerCruiser	350 MAG ALPHA/BRAVO	350	4-Stroke	1986–1997	27-34898
MerCruiser	5.0L MPI ALPHA/BRAVO	5.0L	4-Stroke	Up to 2002	27-34898
MerCruiser	5.7L CARB ALPHA/BRAVO	5.7L	4-Stroke	Up to 2002	27-34898
MerCruiser	5.7L EFI (TBI) GM 350 V-8	5.7L	4-Stroke	1995–1997	27-34898
MerCruiser	350 MAG MPI ALPHA/BRAVO	350	4-Stroke	Up to 2002	27-34898
MerCruiser	377 MAG MPI BRAVO	377	4-Stroke	Up to 2002	27-34898
MerCruiser	MX 6.2L MPI BRAVO	6.2L	4-Stroke	Up to 2002	27-34898
MerCruiser	280 TRS GM 350 V-8 (SKI)	280	4-Stroke	1975–1976	27-34898
MerCruiser	300 TEMPEST GM 350 V-8	300	4-Stroke	1985–1986	27-34898
MerCruiser	350 MAG (SKI) GM 350 V-8	350	4-Stroke	1991–1997	27-34898
MerCruiser	350 MAG MPI SKI	350	4-Stroke	1995–2002	27-34898
MerCruiser	5.7L COMPETITION SKI GM 350 V-8	5.7L	4-Stroke	1987–1997	27-34898
MerCruiser	BLACK SCORPION 350 MAG SKI	350	4-Stroke	1996–2002	27-34898
MerCruiser	BLACK SCORPION MX 6.2L	6.2L	4-Stroke	2001–2002	27-34898
MerCruiser	SCORPION 377	377	4-Stroke	Up to 2002	27-34898
MerCruiser	383 MAG STROKER	383	4-Stroke	All	27-34898	Gen+ Crate Engine

Technical Specs

Product Type: Fuel Pump Mounting Gasket
Installation: Between fuel pump and engine block
Fuel Type: Gasoline
Material: Paper/composite gasket material
Dimensions: 7.13 × 6.0 × 0.13 inches
Weight: 0.009 kg (0.02 lb)

What’s in the Box

1 x Fuel Pump Mounting Gasket (27-34898)

Installation Notes

Disconnect the battery and relieve any pressure from the fuel system.
Carefully disconnect the fuel inlet and outlet lines from the fuel pump.
Remove the fuel pump mounting bolts and detach the pump from the engine block.
Remove the old gasket and thoroughly clean both mating surfaces to remove any residue or debris.
Position the new gasket on the engine block, aligning it with the bolt holes.
Mount the new fuel pump and tighten the bolts to the manufacturer's recommended torque specifications.
Reconnect the fuel lines securely.
Reconnect the battery, start the engine, and carefully check for any fuel leaks around the gasket and fittings.

Troubleshooting & FAQ

How do I know if my fuel pump gasket is failing?

Signs of a failing gasket include visible fuel or oil leaks around the fuel pump mounting area, a strong smell of gasoline, poor engine performance, hesitation, or stalling. A visual inspection is the best way to confirm a leak.

Is this gasket compatible with ethanol-blended fuels?

Yes, this gasket is made from modern composite materials designed to be resistant to standard ethanol-blended gasoline (up to E10). For higher concentrations, always consult your engine manufacturer's recommendations.

Do I need to use a sealant with this gasket?

Generally, this type of gasket is designed to be installed dry. Applying sealant can sometimes cause the gasket to slip or squeeze out, leading to leaks. Always follow the installation guidelines in your engine's service manual.

Will this fit a V6 MerCruiser engine?

Yes, this gasket fits a wide range of V6 and V8 MerCruiser engines. Please refer to the detailed compatibility table to ensure it matches your specific engine model and year.

What is the recommended replacement interval?

There is no specific replacement interval for this gasket. It should be replaced whenever the fuel pump is removed or if a leak is 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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Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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