Exhaust Manifold Riser Elbow Gasket – Fits MerCruiser 4.3L, 5.0L, 5.7L, 5.8L, 6.2L, 7.4L, 8.1L, 8.2L Engines

Exhaust Manifold Riser Elbow Gasket – Fits MerCruiser 4.3L, 5.0L, 5.7L, 5.8L, 6.2L, 7.4L, 8.1L, 8.2L Engines (Replaces 030240)

This replacement exhaust riser gasket is designed for a precise fit on a wide range of MerCruiser V6 and V8 engines manufactured between 1982 and 2002. It is specifically engineered for marine wet-joint exhaust systems, providing a reliable seal between the exhaust manifold and the riser.

This part is a direct replacement for several OEM and aftermarket part numbers, including Great Lakes Memories 030240, Sierra 18-2849-1, Mercury 27-818832, and Mercury 27-863726.

• Installation Location: Mounts between the exhaust manifold and the exhaust riser/elbow.
• Material Construction: Features a durable stainless steel core with a graphite coating on both sides to ensure a tight seal and prevent distortion under pressure.
• Engine Compatibility: Fits both GM-based and Ford-based MerCruiser engines from 1982–2002.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Exhaust Riser Gasket (030240)

Installation Guide

1. Safety First: Ensure the engine is completely cool and disconnect the battery.
2. Drain Coolant: Drain the engine coolant from the manifold to prevent spills.
3. Access the Riser: Remove any components blocking access to the exhaust riser bolts.
4. Remove Riser Bolts: Carefully loosen and remove the bolts connecting the riser to the manifold.
5. Separate Riser: Gently detach the riser from the manifold. It may be stuck; avoid using excessive force.
6. Remove Old Gasket: Peel off the old gasket and discard it.
7. Clean Surfaces: Thoroughly clean both the manifold and riser mating surfaces. Ensure they are free of old gasket material, rust, or debris.
8. Install New Gasket: Position the new gasket correctly on the manifold.
9. Reattach Riser: Carefully place the riser back onto the manifold, aligning the bolt holes.
10. Tighten Bolts: Hand-tighten the bolts first, then torque them to the manufacturer's specified sequence and rating.
11. Reconnect and Refill: Reattach any previously removed components, refill the coolant, and reconnect the battery.
12. Check for Leaks: Start the engine and carefully inspect for any exhaust or water leaks around the gasket.

Troubleshooting & FAQ

How do I confirm this fits my engine?
This gasket fits MerCruiser V6 and V8 engines made from 1982 to 2002. It is designed for wet-joint exhaust systems only and is not compatible with dry-joint systems introduced after 2002. Please verify your engine model and year using the compatibility table.

What is the benefit of the stainless steel core?
The stainless steel core provides rigidity and prevents the gasket from distorting or "blowing out" under the extreme heat and pressure of the exhaust system, ensuring a longer-lasting, reliable seal.

What are the signs my riser gasket is failing?
Common signs of a failed exhaust riser gasket include water leaking externally from the joint, engine overheating, or water entering the engine cylinders, which can cause significant damage. Regular inspection during routine maintenance is recommended.

OEM vs. Aftermarket?
This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?
We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?
This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.