27-863726 Exhaust Full Flow Elbow Gasket for MerCruiser GM V6 & V8

SERDAMARINE / MARINE EXHAUST PARTS

Exhaust Full Flow Elbow Gasket for MerCruiser Wet Joint & Dry Joint Alternative Interfaces

This aftermarket exhaust full-flow elbow gasket seals the exhaust manifold, elbow, and spacer interfaces on specified MerCruiser GM V6 and V8 applications, referenced to OEM 27-863726. It is configured for open full-flow passages in specified wet-joint applications (1981 and up or 1983 through 0M serial numbers, depending on engine family) and designated GM V6/V8 small-block dry-joint alternative configurations (0M serial numbers and up).

This listing is for the gasket component only, not an exhaust manifold or exhaust elbow assembly.

Configuration & Specifications

Engine Applications

This gasket fits the MerCruiser GM V6 and V8 exhaust manifold and spacer applications listed below when the specified joint configuration, year, and serial number boundaries match. Select the gasket by the required part number, engine family, serial number range, and wet-joint or dry-joint alternative configuration rather than by engine displacement alone, and do not treat an open full-flow gasket, a restricted-flow gasket, and a closed-cooling block-off gasket as the same version.

• MerCruiser Model 175–205 (V6, GM 229 / 262 CID) — Years: 1983 through 0M serial numbers. Interface: Exhaust manifold and spacers, Wet Joint, Full Flow (Open) configuration. Fits when specified
• MerCruiser Model 200–320 (V8 Small Block, GM 305 / 350 / 377 CID) — Years: 1983 through 0M serial numbers. Interface: Exhaust manifold and spacers, Wet Joint, Full Flow (Open) configuration. Fits when specified
• MerCruiser Model 330–370 (V8 Big Block, GM 454 / 502 CID) — Years: 1981 & up. Interface: Exhaust manifold and spacers, Wet Joint, Full Flow (Open) configuration. Fits when specified
• MerCruiser GM V6 / V8 Small Block — Serial numbers: 0M & up. Interface: Exhaust manifold and spacers, Dry Joint "Alternative", Full Flow (Open) configuration. Fits when specified

Application Check Required

• 200 (DFI 7 EFI), 200 PRO XS, 225 (EFI / DFI), 225 SEAPRO, 250 (DFI / EFI) 3.0L — Listed in supplementary notes without confirmed brand or exhaust manifold interface details. Verify by OEM part number 27-863726 and physical joint configuration before ordering. Confirm application

Additional model-specific applications

• MerCruiser GM V6, 229 CID, WET JOINT; Application group MODEL 175-205.
• MerCruiser GM V6, 262 CID, WET JOINT; Application group MODEL 175-205.
• MerCruiser GM V8 Small Block, 305 CID, WET JOINT; Application group MODEL 200-320.
• MerCruiser GM V8 Small Block, 350 CID, WET JOINT; Application group MODEL 200-320.
• MerCruiser GM V8 Small Block, 377 CID, WET JOINT; Application group MODEL 200-320.
• MerCruiser GM V8 Big Block, 454 CID, WET JOINT; Application group MODEL 330-370.
• MerCruiser GM V8 Big Block, 502 CID, WET JOINT; Application group MODEL 330-370.
• MerCruiser GM V8 Small Block, DRY JOINT “ALTERNATIVE” configuration, 0M SN#’s & UP.

Reference Numbers

The numbers below are provided for part identification and cross-reference only; they do not by themselves establish guaranteed interchangeability across all exhaust configurations or indicate original manufacturer identity.

Supplied Parts

• Exhaust Full Flow Elbow Gasket

Service & Installation Notes

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

1. Shut off the engine, allow all exhaust components to cool completely, and disconnect the battery to prevent accidental cranking during service.
2. Support heavy exhaust elbows or spacers before loosening fasteners, and remove old gasket material while protecting the machined mating surfaces from scratches or gouges.
3. Compare the new full-flow gasket passages directly against the removed gasket, manifold, elbow, and spacer ports to confirm the open-flow layout matches your cooling and joint configuration; never substitute a full-flow gasket where a restrictor or block-off gasket is required.
4. Align the gasket at the manifold, elbow, or spacer interface and tighten fasteners in the sequence and torque specified by your engine service manual.
5. After reassembly, run the engine only with proper cooling water supply and inspect the joint for exhaust or water leaks; shut down immediately and inspect if any leakage or abnormal temperature 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