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Sierra 18-1204-1 Exhaust Manifold Mounting Gasket for MerCruiser & OMC Stern Drive

Manufacturer

Part Number

18-1204-1
Sale Price

$17.33

In Stock (8)

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-1204-1 is a marine exhaust manifold mounting gasket designed as a direct replacement for MerCruiser and OMC stern drive applications. This gasket seals the exhaust manifold to the cylinder head on GM 2.5L and 3.0L (153 and 181 CID) 4-cylinder engines, helping maintain a leak-free exhaust system and protecting engine components from exhaust gas intrusion.

Key Features:

  • Direct OEM-replacement exhaust manifold mounting gasket
  • Designed for GM 2.5L (153 CID) and 3.0L (181 CID) 4-cylinder marine engines
  • Compatible with non-Vortec cylinder head configurations
  • Sold individually; 2 gaskets are required per manifold installation
  • Meets or exceeds OEM specifications for reliable sealing performance

OEM Cross-Reference Part Numbers:

  • MerCruiser Stern Drive: 27-96429
  • OMC Stern Drive: 912164
  • Mallory: 9-61419
  • GLM: 33570
  • Barr: MC472796429

Compatible With These Sierra Manifolds:

  • Sierra 18-1901
  • Sierra 18-1954-1
  • Sierra 18-1955-1
  • Sierra 18-1956-3

Note: Priced and sold individually. Two gaskets are required per complete manifold installation.

It was easy to use and order from

quick, straight forward, and no BS.

very simple order process

summit wouldn't let me order the part online...I called them and got disconnected during a transfer...turned out it was cheaper through autoplicity and I could order it online and pay via Amazon...awesome

Good

Quick; easy; done

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