Exhaust Elbow Gasket – Fits MerCruiser V6 & V8 (Replaces 27-864547A02, 864547A1)
Exhaust Elbow Gasket – Fits MerCruiser V6 & V8 (Replaces 27-864547A02, 864547A1) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Exhaust Elbow Gasket – Fits MerCruiser V6 & V8 (Replaces 27-864...
Product Details
This high-quality Full Flow Dry Joint Exhaust Elbow Gasket is designed for MerCruiser V6 and V8 stern drive and inboard engines (4.3L, 5.0L, 5.7L, 6.2L, and 6.3L) manufactured from 2002 and newer with dry joint exhaust systems.
It serves as a direct replacement for MerCruiser part numbers 27-864547A02 and 27-864547A1, and Sierra 18-0721.
- Installation Type: Dry Joint
- Gasket Style: Full Flow (Open) for unrestricted cooling
- Material: Durable metal construction for a reliable seal
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 27-864547A02 |
| MerCruiser | 864547A1 |
| Sierra | 18-0721 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This gasket is compatible with the following MerCruiser models equipped with dry joint exhausts from 2002 onwards.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 350 MAG | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
| MerCruiser | 4.3L | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
| MerCruiser | 5.0L | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
| MerCruiser | 5.7L | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
| MerCruiser | 6.2L | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
| MerCruiser | 6.3L | Various | 4-Stroke | 2002 and newer | 27-864547A02 | Dry joint exhaust manifolds only |
Technical Specs
- Product Type
- Exhaust Elbow/Riser Gasket
- Installation
- Dry Joint Type
- Gasket Style
- Full Flow (Open)
- Material
- Metal
- Shape
- Rectangular
- Application
- Exhaust Manifold to Elbow/Riser
- Engine Type
- V6 & V8 MerCruiser Stern Drive and Inboard Engines
- Engine Compatibility
- 4.3L, 5.0L, 5.7L, 6.2L, 6.3L
- Engine Year Range
- 2002 and newer
What’s in the Box
- 1 x Dry Joint Gasket Open (27-864547A02)
Installation Notes
- Disconnect the negative battery terminal for safety.
- If applicable, drain the engine coolant from the exhaust manifold to a level below the riser.
- Carefully unbolt and remove the exhaust elbow/riser from the manifold.
- Remove the old gasket. Thoroughly clean and inspect both mating surfaces, ensuring they are free of old gasket material, corrosion, and debris.
- Position the new full flow dry joint gasket correctly onto the manifold.
- Reinstall the exhaust elbow/riser. Tighten the bolts in the sequence and to the torque specifications recommended by the manufacturer.
- Reconnect any cooling hoses that were removed.
- Refill the cooling system if it was drained.
- Reconnect the battery cable.
- Start the engine and carefully check for any exhaust or water leaks around the gasket joint.
Troubleshooting & FAQ
How do I know if I need a "dry joint" gasket?
Dry joint exhaust systems became standard on MerCruiser V6 and V8 engines from 2002 onwards. Visually, the mating surfaces are flat and the gasket does not have integrated water passages. Always confirm your engine model and year before ordering.
What is the difference between this "full flow" (open) gasket and a restricted one?
This full flow (open) gasket is for systems where coolant flow is not restricted at the riser, typical for freshwater cooled engines. Restricted gaskets are used in some raw water cooled systems to regulate engine temperature. Using the wrong type can cause overheating or overcooling.
What are common signs that my exhaust elbow gasket is failing?
Telltale signs include water leaking externally from the joint between the manifold and elbow, steam from the engine compartment, engine overheating, or finding water in the engine oil (which indicates a serious internal leak).
How often should I replace this gasket?
There is no fixed service interval. It is best practice to replace the gasket any time the exhaust riser or manifold is removed for service. In saltwater applications, it's wise to inspect the exhaust system more frequently (e.g., every 1-2 years) for corrosion and leaks.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in 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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
