27-18272 Exhaust Elbow Riser Gasket 2-Pack for MerCruiser 3.7L 4-Cyl

SERDAMARINE / MARINE EXHAUST PARTS

Manifold Riser Gasket Pack for MerCruiser 3.7L and 4-Cylinder Exhaust Applications

This two-piece replacement sealing gasket pack (referencing MerCruiser OEM 27-18272) services the exhaust elbow and manifold riser mounting joint on compatible MerCruiser 4-cylinder engines. Application eligibility depends on whether the engine is equipped with an aluminum manifold (1985–1989 3.7L 170/470) or a cast-iron manifold (excluding 1976–1982 470 models).

Engine Applications

Cast-iron and aluminum manifold versions must not be selected by engine displacement, cylinder count, or model number alone. Check whether your exhaust manifold is cast iron or aluminum and verify the gasket reference number before ordering.

• MerCruiser 3.7L 4-Cylinder (Models 170 / 470) — 1985–1989. Requires aluminum exhaust manifold configuration. Fits when specified
• MerCruiser 4-Cylinder Engines — Requires cast-iron exhaust manifold configuration. Excludes 1976–1982 model 470. Fits when specified
• MerCruiser 3.7L & 3.7LX MCM (Models 165, 170, 180, 190, 470, 485, 488) — 224 CID, 4-cylinder, 1980–1989 manifold, elbow, end-cap, and gasket service family. Must match the specific cast-iron or aluminum manifold requirements and exclusion years listed above. Fits when specified

Not Suitable For

• MerCruiser 470 (4-Cylinder with Cast-Iron Manifold) — 1976–1982. Not suitable

Additional model-specific applications

• MerCruiser 3.7L MCM, 224 CID, four-cylinder, listed within the 1980–1989 manifold/elbow application group.

Reference Numbers

These part numbers are provided as identification references and do not by themselves guarantee interchangeability across different manifold configurations or indicate original manufacturer identity.

Supplied Parts

• 2 × Exhaust elbow / manifold riser mounting gasket

Service & Installation Notes

General service guidance only. Use the service manual for your exact engine and exhaust configuration.

1. Ensure the engine is completely shut off, cooled down, and secured against accidental starting before loosening any exhaust components.
2. Support the exhaust elbow or riser assembly during removal and reinstallation to prevent strain on mating joints or adjacent connections.
3. Clean old gasket material from the manifold and elbow mating surfaces carefully, protecting the sealing planes from gouges or scratches, especially on aluminum manifolds.
4. Compare the new gasket profile and port openings directly against both the manifold and riser mating surfaces before final assembly.
5. Tighten mounting fasteners according to the sequence and specifications in your engine service manual, and stop operation immediately to inspect the joint if any exhaust or sealing abnormality is observed.

The Serdamarine Approach

Exhaust parts need a configuration match. Serdamarine focuses on marine exhaust manifolds and their related service parts. Application details, connection requirements and public reference numbers are presented together to support part selection.

Questions Before Replacement