This article recommends three aftermarket dry joint MerCruiser exhaust elbow/riser gaskets. You can choose to schedule an order with us on our website or directly order from the Amazon link provided. Additionally, there is a brief introduction about the application engines, material, and replacement timing for the exhaust elbow/riser gasket.
If you need a MerCruiser 4.3 exhaust riser gasket or a MerCruiser 5.7 exhaust riser gasket, the products mentioned in this article can meet your needs perfectly.
About Wet Joint and Dry Joint
First, let’s explain what a “Dry Joint” is. This term refers to a design feature in certain MerCruiser engines. In a dry joint exhaust system, the exhaust gases and cooling water are kept separate to reduce corrosion and extend the lifespan of the exhaust manifold.
Wet joints have caused thousands of engine failures over the years. The water galleries are just millimeters from the exhaust passages, making the gaskets prone to failure. As exhaust manifolds and risers expand and contract with heat, the gaskets eventually fail. This can lead to water leakage, causing corrosion or internal engine damage. Overheating worsens the issue, distorting metal surfaces and ensuring engine failure. Wet joints were used until the early 2000s, and Volvo still uses them. Wet joint manifolds and risers require gasket replacement every two years and often fail at the gasket surfaces. Mercruiser wet joint manifolds should be upgraded to the newer dry joint style when due for replacement. Volvo continues to use wet joint manifolds and risers on most of their petrol engines.
Gaskets are crucial in the exhaust systems of marine engines. There are two main types: dry joint and wet joint. Dry joints have a longer lifespan, typically lasting 5 to 7 years, and it’s recommended to inspect their internal condition every 3 to 4 years. Wet joints have a shorter lifespan, about 5 years, and it’s advised to replace their gaskets every two years.
MerCruiser GM V6/V8 engines cooling systems
MerCruiser GM V6/V8 engines utilize two primary types of cooling systems: raw water cooling and fresh water (closed-loop) cooling.
- Raw Water Cooling: This system directly uses water from the surrounding environment (lake, river, or ocean) to cool the engine. The water is drawn into the engine, circulated to absorb heat, and then expelled back into the environment. This method is simpler and less expensive, but it exposes the engine to potential corrosion and damage from impurities or salt in the water.
- Fresh Water (Closed-Loop) Cooling: In this system, the engine is cooled by a mixture of water and antifreeze that circulates within a closed loop. A heat exchanger transfers the heat from this coolant to the raw water, which then expels the heat outside. This type of system is more effective at preventing corrosion and is better for longevity and performance, especially in saltwater environments.
Both systems are designed to cool the engine effectively, but the closed cooling system is considered more efficient and easier to maintain.
Full Flow Gasket/Elbow Block Off Gasket/Elbow Restrictor Flow Gasket
MerCruiser Dry joint – Full Flow Exhaust Elbow Riser Gasket
A full-flow exhaust elbow gasket allows cooling water or seawater to flow freely through the space between the exhaust manifold and the exhaust riser.
MerCruiser Dry joint – Closed Cooling Exhaust Elbow Riser Gasket
A closed cooling exhaust elbow gasket prevents cooling water or seawater from flowing through the space between the exhaust manifold and the exhaust riser.
MerCruiser Dry joint – Restricted Flow Exhaust Elbow Riser Gasket
A restricted-flow exhaust elbow gasket allows a limited amount of cooling water or seawater to flow through the space between the exhaust manifold and the exhaust riser.
The purpose of the restrictor hole is to prevent the cold bypass water as it enters the exhaust elbow, from back-flowing down and into the manifolds. If the restrictor hole is positioned incorrectly the cold bypass water will flow downward into the manifold and prevent the manifold temperatures from heating up enough to prevent condensation.
The image below shows, from left to right, a Full Flow Gasket, an Elbow Block Off Gasket, and an Elbow Restrictor Flow Gasket. The obvious differences lie in the holes at the top, which are respectively fully open, completely closed, and have a small hole.
Gasket Installation Locations
The Exhaust Elbow/Riser Gasket is installed in two places from top to bottom: between the Exhaust Elbow and the Riser, and between the Riser and the Exhaust Manifold.
Engine Applications
MerCruiser GM V‑6 & V‑8 4.3/5.0/5.7/6.2L Engines with dry joint exhaust manifold. (2002 and newer)
Gasket Material
Metal Bonded with Rubber
When Exhaust Elbow/Riser Gasket Need Replacement?
Maintenance recommendations suggest that experienced boat owners verify the condition of risers by removing and inspecting the elbows. If there are no reliable maintenance records, it’s advised to proactively replace the raw water impeller. For freshwater use, these components can last a long time. However, in saltwater use, one boat owner shared that the failure rate drops to 25% after four years, recommending regular replacement to prevent engine failure.
Where to buy Mercruiser Dry-Joint Exhaust Elbow/Riser Gasket
Looking to upgrade your MerCruiser engine’s performance and ensure long-lasting reliability? Check out these top-quality MerCruiser dry-joint gaskets from BearTheSealer, specifically designed for 4.3/5.0/5.7/6.2L engines. BearTheSealer is renowned for its dedication to high-quality manufacturing, ensuring you get the best performance and durability for your engine. Don’t settle for subpar gaskets. Choose our top-rated dry-joint gaskets for optimal performance, durability, and ease of installation. Order now and experience the difference for yourself.
BTS-27-864547A02 Full Flow Gasket 4.3/5.0/5.7/6.2L
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BTS-27-864549A02 Elbow Block Off Gasket for MerCruiser
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BTS-27-864850A02 Elbow Restrictor Gasket 4.3/5.0/5.7/6.2L
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About BEAR THE SEALER
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Bear the Sealer, we believe that quality is the key point to our success. Our brand can grow rapidly is because we choose our suppliers very carefully around the world. There are many aftermarket gaskets available in the market, but we stand out by ensuring that our gaskets are of the highest quality possible.
We use only the best materials and work closely with our suppliers to ensure that they meet our stringent quality control standards. We take quality so seriously. Our customers can trust that our gaskets will perform reliably and efficiently, ensuring that their operations run smoothly.
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