27-99757 Exhaust Manifold-to-Head Gasket Set for MerCruiser 4.3L 4.5L

SERDAMARINE / MARINE EXHAUST PARTS

Exhaust Manifold-to-Cylinder Head Gasket Set, 2 Pieces

This two-piece gasket set is used to seal the exhaust manifold-to-cylinder head joint on matching MerCruiser, Volvo Penta, and OMC Cobra stern drive applications, including listed V6 4.3L and 4.5L engines, referencing OEM part number 27-99757. These gaskets install between the exhaust manifold and cylinder head—not at the manifold-to-elbow or manifold-to-riser joint—and listed Dry Joint applications are distinguished by year group and exhaust configuration (2002–2004 7° and 2005–2010 14°).

Configuration & Specifications

Engine Applications

This gasket set is associated with MerCruiser Stern / Out Drive, OMC Cobra Stern / Out Drive, and Volvo Penta Stern / Out Drive applications, including V6 4.3L and 4.5L engines, as well as the specific GM and Chevy engine groups listed below. Select the gasket by the engine-specific part number, full serial number (especially for 0M serial-number boundaries), year group, and exhaust-system configuration rather than displacement alone.

• MerCruiser Stern / Out Drive, OMC Cobra Stern / Out Drive, Volvo Penta Stern / Out Drive — V6 4.3L and 4.5L Applications — Applicable where the engine parts list specifies a matching exhaust manifold-to-cylinder head gasket reference number. Fits when specified — Must match required OEM gasket part number and manifold-to-cylinder head joint position
• GM 229 / 262 CID — MODEL 175-205 - V6 — Years: 1983 - 0M SN#’s. Fits when specified — Verify 1983 to 0M serial-number range and required gasket reference
• Chevy V6 — Exhaust manifold-to-cylinder head sealing joint. Fits when specified — Match exact engine model and required gasket part number
• GM V6 & V8 S.B. Dry Joint (2002–2004) — Exhaust configuration: 7° (2002–2004). Fits when specified — Dry Joint system, 2002–2004 7° configuration at the manifold-to-cylinder head joint
• GM V6 & V8 S.B. Dry Joint (2005–2010) — Exhaust configuration: 14° (2005–2010). Fits when specified — Dry Joint system, 2005–2010 14° configuration at the manifold-to-cylinder head joint
• GM V6 & V8 S.B. — Dry Joint Exhaust Manifold & Elbow Gaskets Category — For the exhaust manifold-to-cylinder head joint within this category. Fits when specified — For the manifold-to-cylinder head joint only; not for the manifold-to-elbow joint
• GM V6/V8 S.B. DRY JOINT “ALTERNATIVE” — Serial numbers: 0M SN#’s & UP. Fits when specified — Dry Joint “ALTERNATIVE” configuration, 0M serial numbers and up

Additional model-specific applications

• MerCruiser V6, GM 229 CID application; Application group: MODEL 175-205 — V6, GM 229/262 CID (1983 - 0M SN#’s).
• MerCruiser V6, GM 262 CID application; Application group: MODEL 175-205 — V6, GM 229/262 CID (1983 - 0M SN#’s).
• MerCruiser GM V6 S.B., 2002–2004, Dry Joint, 7°.
• MerCruiser GM V8 S.B., 2002–2004, Dry Joint, 7°.
• MerCruiser GM V6 S.B., 2005–2010, Dry Joint, 14°.
• MerCruiser GM V8 S.B., 2005–2010, Dry Joint, 14°.
• MerCruiser, GM-based application, V6 S.B., Dry Joint Exhaust Manifold & Elbow Gaskets section.
• MerCruiser, GM-based application, V6 S.B., Dry Joint “Alternative,” 0M serial series and up.

Reference Numbers

The numbers below are provided for part identification and cross-reference only; they do not by themselves guarantee interchangeability across every engine configuration or indicate the manufacturer of this aftermarket set. Keep all prefixes, suffixes, and leading zeros when comparing your original part number.

Supplied Parts

• Exhaust manifold-to-cylinder head gaskets (2 pieces)

Service & Installation Notes

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

1. Allow the engine and exhaust system to cool completely, shut off the battery switch, and secure the ignition to prevent accidental starting.
2. Support the weight of the exhaust manifold during removal and installation to avoid damaging mounting threads or mating surfaces.
3. Remove all old gasket material and clean both the cylinder head and exhaust manifold mating surfaces carefully without gouging the metal.
4. Position the new gaskets at the exhaust manifold-to-cylinder head joint—do not install them at the manifold-to-elbow or manifold-to-riser joint—and verify port alignment.
5. Install and tighten the manifold fasteners in the sequence and to the specification given in your engine service manual; after starting, inspect for exhaust leaks and stop the engine immediately if any abnormal condition occurs.

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