Full Flow Elbow Gasket – Fits MerCruiser GM V-6 & V-8 (Replaces 27-864547A02, 27-864547A1)
Full Flow Elbow Gasket – Fits MerCruiser GM V-6 & V-8 (Replaces 27-864547A02, 27-864547A1) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
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Full Flow Elbow Gasket – Fits MerCruiser GM V-6 & V-8 (Replaces...
Full Flow Elbow Gasket – Fits MerCruiser GM V-6 & V-8 (Replaces 27-864547A02, 27-864547A1) is backordered and will ship as soon as it is back in stock.
Product Details
This Full Flow Elbow Gasket – Fits MerCruiser GM V-6 & V-8 Stern Drives with Risers (Replaces 27-864547A02, 27-864547A1) is designed for MerCruiser GM V-6 and V-8 engines (2002 & newer) that feature a dry joint exhaust manifold and utilize standard cooling. It is compatible with 4.3L, 5.0L, 5.7L, and 6.2L models equipped with risers.
This part provides a direct replacement for MerCruiser part numbers 27-864547A02 and 27-864547A1, as well as Sierra 18-0721.
- Engineered for modern dry joint exhaust systems.
- Full flow (open) style for standard cooling applications.
- Designed exclusively for use with exhaust risers.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 27-864547A02 |
| MerCruiser | 27-864547A1 |
| Sierra | 18-0721 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For MerCruiser owners, this gasket fits V-6 and V-8 gas stern drives manufactured from 2002 onwards with the dry joint exhaust system.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 4.3L | 4.3L | 4-Stroke | 2002 & Newer | 27-864547A02/27-864547A1 | Dry Joint Manifold with Risers |
| MerCruiser | 5.0L | 5.0L | 4-Stroke | 2002 & Newer | 27-864547A02/27-864547A1 | Dry Joint Manifold with Risers |
| MerCruiser | 5.7L | 5.7L | 4-Stroke | 2002 & Newer | 27-864547A02/27-864547A1 | Dry Joint Manifold with Risers |
| MerCruiser | 350 MAG | 5.7L | 4-Stroke | 2002 & Newer | 27-864547A02/27-864547A1 | Dry Joint Manifold with Risers |
| MerCruiser | 6.2L | 6.2L | 4-Stroke | 2002 & Newer | 27-864547A02/27-864547A1 | Dry Joint Manifold with Risers |
Technical Specs
- Product Type
- Exhaust Elbow Gasket
- Installation
- Dry Joint System
- Style
- Full Flow (Open)
- Application
- Standard Cooling
- Material
- Metal
- Shape
- Rectangular
- Cooling Type
- Standard Cooling
- Exhaust Type
- Dry Joint
- Other Technical Attributes
- Used with risers only
What’s in the Box
- 1 x Riser Gasket (Open) (27-864547A02/27-864547A1)
Installation Notes
- Ensure both the manifold and riser mating surfaces are perfectly clean and free of old gasket material, residue, or corrosion.
- Place the new gasket into position, confirming its orientation matches the cooling passages. This is a full-flow gasket, so all passages will be open.
- Carefully mount the riser, ensuring it aligns correctly without shifting the gasket.
- Install mounting bolts and tighten them to the manufacturer's recommended torque specifications using a calibrated torque wrench. Follow the specified tightening sequence to ensure even pressure.
Troubleshooting & FAQ
How do I know if I need a "full flow" or "restrictor" gasket?
This full flow (open) gasket is for engines with standard or raw water cooling systems. If your engine uses a closed cooling (freshwater) system, you would typically need a restrictor gasket (such as Sierra 18-0720) to regulate coolant flow. Always check your service manual to confirm the correct type for your specific setup.
Will this gasket fit an engine older than 2002?
No, this gasket is specifically designed for MerCruiser's dry joint exhaust system, which was introduced in 2002. It is not compatible with earlier wet joint systems.
What are the signs of a failing elbow gasket?
Common symptoms include visible water leaks (especially when the engine is running), rust stains originating from the joint, engine overheating, or, in severe cases, water intrusion into the cylinders, which can cause catastrophic engine damage. Regular inspection is recommended.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). It has been built to OEM-level specifications with comparable materials. Our parts are manufactured in an ISO 9002 facility and are batch-inspected for quality and consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options will appear at checkout where available for your location.
Warranty & returns
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its 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.
Payment & Security
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