Full Flow Riser Elbow Gasket – Fits MerCruiser V6 & V8 Marine Engines (Replaces 27-863726)
Full Flow Riser Elbow Gasket – Fits MerCruiser V6 & V8 Marine Engines (Replaces 27-863726) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Full Flow Riser Elbow Gasket – Fits MerCruiser V6 & V8 Marine E...
Product Details
This Full Flow Riser Elbow Gasket is engineered for MerCruiser 4.3L, 5.0L, 5.7L, 6.2L, 7.4L, and 8.2L V6 and V8 engines equipped with center rise outlet exhaust manifolds, covering models from 1998–2001. It ensures a reliable seal between the exhaust manifold and the riser.
It serves as a direct replacement for multiple part numbers, including Mercury/MerCruiser 27-863726, Sierra 18-2849-1, Mallory 9-61414, and GLM 32080.
- Designed for a completely open, full-flow connection.
- Installs between the manifold and riser.
- Engineered for marine environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/MerCruiser | 27-863726 |
| Mercury/MerCruiser | 27-818832 |
| Mercury/MerCruiser | 27-860232 |
| Mercury/MerCruiser | 27-87105 |
| Mercury/MerCruiser | 27-871051 |
| Sierra | 18-2849-1 |
| Mallory | 9-61414 |
| GLM | 32080 |
| Barr | MC47-27-87105 |
| Osco | 8503-GO |
| Pro Marine | 863726 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury/MerCruiser Models: Please verify your engine's serial number (S/N) falls within the specified range for accurate fitment.
| Brand | Model | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| Mercury/MerCruiser | 4.3L (GEN+) 2 BBL. | 1998 | 27-863726 | S/N 0L010044 THRU 0M614999 |
| Mercury/MerCruiser | 4.3L (GEN+) 4BBL Reman | 2009 | 27-863726 | S/N 1G400000 & Up |
| Mercury/MerCruiser | 4.3L EFI (GEN+) TBI | 1998 | 27-863726 | S/N 0L619000 THRU 0M322780 |
| Mercury/MerCruiser | 4.3L MPI ALPHA/BRAVO | 27-863726 | S/N 0M300000 THRU 0M614999 | |
| Mercury/MerCruiser | 4.3LH (GEN+) 4 BBL. | 1998 | 27-863726 | S/N 0L010044 THRU 0M614999 |
| Mercury/MerCruiser | 5.0L (2 BBL.) | 1988–2001 | 27-863726 | S/N 0L015751 THRU 0M599999 |
| Mercury/MerCruiser | 5.0L EFI | 1998–2001 | 27-863726 | S/N 0L331631 THRU 0M299999 |
| Mercury/MerCruiser | 5.0L MPI ALPHA/BRAVO | 27-863726 | S/N 0M300000 THRU 0M599999 | |
| Mercury/MerCruiser | 5.7L (2 BBL.) | 1988–2001 | 27-863726 | S/N 0L010037 THRU 0M599999 |
| Mercury/MerCruiser | 5.7L CARB MIE | 27-863726 | S/N 0L002003 THRU 0M316999 | |
| Mercury/MerCruiser | 5.7L COMPETITION SKI (GEN+) | 1998 | 27-863726 | S/N 0L002005 THRU 0M316999 |
| Mercury/MerCruiser | 5.7L EFI | 1997–2001 | 27-863726 | Multiple serial ranges |
| Mercury/MerCruiser | 350 MAG MPI ALPHA/BRAVO | 27-863726 | Multiple serial ranges | |
| Mercury/MerCruiser | 350 MAG MPI HORIZON ALPHA/BRAVO | 1998 | 27-863726 | S/N 0M300000 THRU 0M599999 |
| Mercury/MerCruiser | 350 MAG MPI HORIZON MIE | 1998 | 27-863726 | Multiple serial ranges |
| Mercury/MerCruiser | 350 MAG MPI MIE | 27-863726 | Multiple serial ranges | |
| Mercury/MerCruiser | 357 ALPHA 4V | 2008–2009 | 27-863726 | S/N 1G400000 & Up |
| Mercury/MerCruiser | 357 MAG BRAVO 4V | 2008–2009 | 27-863726 | S/N 1G400000 & Up |
| Mercury/MerCruiser | 383 MAG BRAVO 4V | 27-863726 | S/N 1G480748 & Up | |
| Mercury/MerCruiser | MX 6.2L MPI BRAVO | 27-863726 | S/N 0M300000 THRU 0M599999 | |
| Mercury/MerCruiser | MX 6.2L MPI HORIZON BRAVO | 27-863726 | S/N 0M300000 THRU 0M599999 | |
| Mercury/MerCruiser | MX 6.2L MPI HORIZON MIE | 27-863726 | S/N 0M310000 THRU 0M316999 | |
| Mercury/MerCruiser | MX 6.2L MPI MIE | 27-863726 | Multiple serial ranges | |
| Mercury/MerCruiser | 454 MAG MPI BRAVO (GEN VI) | 1998 | 27-863726 | S/N 0L010029 THRU 0L058399 |
| Mercury/MerCruiser | 454 MAG MPI HORIZON (GEN VI) | 27-863726 | S/N 0L086050 THRU 0L674000 | |
| Mercury/MerCruiser | 7.4L BRAVO (MPI)(GEN VI) | 1998–2000 | 27-863726 | S/N 0L010003 THRU 0M024330 |
| Mercury/MerCruiser | 7.4L MPI MIE (L29) GEN VI | 1998–2000 | 27-863726 | S/N 0L002006 THRU 0L674613 |
| Mercury/MerCruiser | 502 MAG MPI BRAVO (GEN VI) | 1998 | 27-863726 | S/N 0L017000 THRU 0L085432 |
| Mercury/MerCruiser | 8.2L MIE MPI (GEN VI) | 27-863726 | S/N 0L086013 THRU 0L674200 | |
| Mercury/MerCruiser | BLACK SCORPION 350 MAG SKI (GEN+) | 1997–2001 | 27-863726 | S/N 0K040001 THRU 0M391599 |
| Mercury/MerCruiser | BLACK SCORPION MX 6.2L SKI (GEN+) | 2001–2002 | 27-863726 | S/N 0L670015 THRU 0M391599 |
Technical Specs
- Product Type
- Exhaust Elbow Gasket
- Installation
- Between manifold and riser
- Connection
- Full flow, 4-slot design
- Dimensions
- 0.5" H × 12.0" W × 18.0" L
- Fitting Type
- Center rise outlet exhaust manifold
- Other Attributes
- Completely open gasket for Full Flow engines only
What’s in the Box
- 1 x Gasket (27-863726)
Installation Notes
- Ensure the engine is completely cool and disconnect the battery.
- Drain the engine coolant to a level below the exhaust manifolds.
- Carefully remove the exhaust riser/elbow from the exhaust manifold.
- Clean both mating surfaces thoroughly, removing all old gasket material and corrosion.
- Place the new gasket onto the manifold, ensuring proper alignment with the bolt holes and passages.
- Reinstall the riser/elbow and tighten the bolts to the manufacturer's specified torque in the correct sequence.
- Refill the cooling system, reconnect the battery, and start the engine.
- Check for any exhaust or water leaks around the gasket area.
Troubleshooting & FAQ
How do I know if this is the right gasket for my engine?
This is a "full flow" gasket, meaning it's completely open. It fits specific MerCruiser V6 and V8 engines from 1998–2001 with center rise manifolds. It is critical to verify your engine model and serial number against the compatibility list. Do not use this part if your engine requires a restricted or water-blocking gasket.
What are the signs of a failed riser gasket?
Common symptoms include water leaking externally from the joint between the manifold and riser, water in the engine oil (milky oil), engine overheating, or steam from the exhaust. If you notice any of these signs, inspect the gasket and surrounding components immediately to prevent catastrophic engine damage.
Can I reuse my old riser bolts?
It is strongly recommended to use new bolts when replacing exhaust gaskets. Old bolts can stretch, corrode, or fatigue, leading to improper torque and potential leaks. Always apply thread sealant to the new bolts if required by your service manual.
How often should riser gaskets be replaced?
Replacement interval depends heavily on usage and environment (freshwater vs. saltwater). As a general rule, inspect your exhaust system annually. Gaskets should be replaced whenever the risers are removed or every 3-5 years in saltwater environments as part of preventative maintenance.
Is any sealant needed with this gasket?
Generally, these gaskets are designed to be installed dry. Applying sealant can sometimes interfere with the seal. However, always consult your engine's specific service manual, as recommendations can vary.
What is the difference between a full flow and a restricted gasket?
A full flow gasket has large, open passages for coolant. A restricted gasket has smaller passages to control water flow, typically used in specific cooling system configurations (like closed cooling systems). Using the wrong type can lead to engine overheating or improper cooling.
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.
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