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FLASHSALE26

Exhaust Manifold Gasket – Fits MerCruiser V8 Small Block 5.0L, 5.7L, 6.2L (Replaces 27-33395)

Regular price $13.90

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Product Details

This Exhaust Manifold Gasket – Fits MerCruiser V8 Small Block 5.0L, 5.7L, 6.2L (Replaces 27-33395) is engineered for a precise seal on V8 (283, 305, 350, 377 CID) engines manufactured by General Motors for MerCruiser stern drives and inboards. It ensures a direct-fit replacement between the exhaust manifold and the cylinder head.

It serves as a direct interchange for Mercury part numbers 27-33395 and 96306, as well as Quicksilver 27-33395.

  • Designed for manifolds with 4 mount bolts.
  • Made from a durable composite material to withstand the marine environment.
  • Provides a reliable seal to prevent exhaust leaks.

Part Number Matrix

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

Brand Part Number
Mercury 27-33395
Mercury 96306
Quicksilver 27-33395

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For MerCruiser applications, this gasket fits a wide range of V8 small block models. Verify your specific engine CID.

Brand Model Rated HP Stroke Years OEM Part No. Notes
MerCruiser V8 (283 CID) 4-Stroke 27-33395 Gasket between manifold and cylinder head
MerCruiser V8 (305 CID) 4-Stroke 27-33395 Gasket between manifold and cylinder head
MerCruiser V8 (350 CID) 4-Stroke 27-33395 Gasket between manifold and cylinder head
MerCruiser V8 (377 CID) 4-Stroke 27-33395 Gasket between manifold and cylinder head

Technical Specs

Product Type
Exhaust Manifold to Head Gasket
Installation
Direct fit between manifold and cylinder head
Material
Composite
Thickness
1/16 inch (1.59 mm)
Density
1.309 g/cm³
Compressibility
15-35%
Recovery
20% Min.
Mounting
For manifolds with 4 mount bolts
Product Dimensions
20.1 × 4.7 × 2.0 inches (51 × 12 × 5 cm)
Weight
0.13 lbs (0.059 kg)

What’s in the Box

  • 1 × Exhaust Manifold Gasket (27-33395)

Installation Notes

  1. Disconnect the battery and allow the engine to cool completely.
  2. Drain the engine cooling system to a level below the exhaust manifolds.
  3. Carefully disconnect any hoses, wires, or sensors attached to the exhaust manifold.
  4. Remove the manifold mounting bolts and detach the manifold from the cylinder head.
  5. Thoroughly clean both the cylinder head and manifold mating surfaces. Remove all old gasket material and debris.
  6. Position the new gasket onto the cylinder head, ensuring it aligns with the bolt holes and exhaust ports.
  7. Carefully place the exhaust manifold over the new gasket.
  8. Install the mounting bolts and tighten them in the sequence and to the torque specifications recommended by the manufacturer.
  9. Reconnect all hoses, wires, and sensors.
  10. Refill the cooling system.
  11. Start the engine and carefully check for any exhaust or coolant leaks around the manifold.

Troubleshooting & FAQ

How do I confirm this gasket fits my specific engine?

The best method is to cross-reference the OEM part number (27-33395) with your engine's service manual. Additionally, check the Engine & Model Compatibility table on this page and compare the specifications and images to your old part.

What are common signs of a failed exhaust manifold gasket?

Symptoms include a loud ticking or hissing noise from the engine bay (especially when cold), a smell of exhaust fumes in the cabin or engine compartment, decreased engine performance or fuel efficiency, and visible soot or black streaks around the manifold-to-head connection.

Is any sealant needed with this gasket?

Generally, this type of composite gasket is designed to be installed dry. Applying sealant can interfere with its ability to compress and seal correctly. Always follow your engine manufacturer's 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

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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