Exhaust Manifold End Cap Gasket – Fits MerCruiser 2.5L/3.0L 4-Cylinder Engines (Replaces 27-807218)
Exhaust Manifold End Cap Gasket – Fits MerCruiser 2.5L/3.0L 4-Cylinder Engines (Replaces 27-807218) is backordered and will ship as soon as it is back in stock.
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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
Product Details
This high-quality Exhaust Manifold End Cap Gasket is designed for MerCruiser GM 2.5L and 3.0L inline 4-cylinder petrol engines, including 3.0L Alpha One, 3.0L/LX, and 3.0L TKS Alpha One Plus Series models. It provides a reliable seal for the exhaust manifold end cap, preventing water and exhaust leaks.
This part serves as a direct replacement for OEM part number 27-807218 and offers cross-reference compatibility with GLM 18-0928, GLM 18-0928-1, and Sierra 18-0928.
- Installation: Engineered for a direct-fit replacement.
- Application: Seals the exhaust manifold end cap.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/Quicksilver | 27-807218 |
| Mercury/Quicksilver | 807218 |
| Mercury/Quicksilver | 2773814 |
| Mercury/Quicksilver | 27738141 |
| GLM | 18-0928 |
| GLM | 18-0928-1 |
| Sierra | 18-0928 |
Engine & Model Compatibility
Confirm your engine model/year in the table below. For further verification, check compatibility by serial number in the second table.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| MerCruiser | 3.0L Alpha One | 3.0L (181 I/L4) | 4-Stroke | 27-807218 | |
| MerCruiser | 3.0L/LX Alpha One | 3.0L (181 I/L4) | 4-Stroke | 1996–1997 | 27-807218 |
| MerCruiser | 3.0L TKS Alpha One Plus Series | 3.0L | 4-Stroke | 27-807218 | |
| MerCruiser | 3.0L/LX Alpha One | 3.0L (181 I/L4) | 4-Stroke | 1998 | 27-807218 |
| MerCruiser | 3.0L GM 181 I/L4 | 3.0L | 4-Stroke | 27-807218 | |
| MerCruiser | 2.5L GM | 2.5L | 4-Stroke | 27-807218 |
| Brand | Model | Serial Number Range | OEM Part No. |
|---|---|---|---|
| MerCruiser | 3.0L GM 181 I/L4 | 0L097000 THRU 0W301999 | 27-807218 |
| MerCruiser | 3.0L GM 181 I/L4 | 0W302000 THRU 1A0019999 | 27-807218 |
| MerCruiser | 3.0L GM 181 I/L4 | 1A002000 THRU 1A020543 | 27-807218 |
| MerCruiser | 3.0L GM 181 I/L4 | 1A020544 & Up | 27-807218 |
| MerCruiser | 3.0L GM 181 I/L4 1 1998 | 0L010042 THRU 0L096999 | 27-807218 |
| MerCruiser | 3.0LX GM 181 I/L4 1996–1997 | 0F604000 THRU 0K999999 | 27-807218 |
| MerCruiser | 3.0L TKS Plus | 1G404114 & Up | 27-807218 |
Technical Specs
- Product Type
- Exhaust Manifold End Cap Gasket
- Installation
- Direct replacement
- Application
- Exhaust manifold end cap
- Engine Type
- MerCruiser GM 181 I/L4 (2.5L & 3.0L) 4-cylinder engines
- Dimensions
- 7.13 in x 6.0 in x 1.13 in
- OEM Part Number
- 27-807218
- Alternate Part Numbers
- 807218, 2773814, 27738141
What’s in the Box
- 1 x Exhaust Manifold End Cap Gasket (27-807218)
Installation Notes
For a secure, leak-free installation, follow these general steps. Always refer to your engine's service manual for detailed instructions and torque specifications.
- Disconnect the battery and allow the engine to cool completely before starting.
- Drain the engine coolant to a level below the exhaust manifold.
- Remove any components obstructing access to the exhaust manifold end cap.
- Carefully unbolt and remove the end cap. Note the orientation of the bolts if they differ in length.
- Thoroughly clean all old gasket material and residue from both the end cap and the manifold sealing surfaces.
- Position the new gasket correctly onto the manifold. Ensure it is properly aligned with the bolt holes.
- Reinstall the end cap and tighten the bolts to the manufacturer's specified torque in the correct sequence.
- Refill the cooling system with the appropriate coolant.
- Reconnect the battery.
- Start the engine and carefully inspect for any water or exhaust leaks around the end cap area.
Troubleshooting & FAQ
How do I know if this gasket fits my engine?
This gasket fits MerCruiser 2.5L and 3.0L 4-cylinder engines as detailed in the compatibility tables. The most reliable method is to cross-reference the OEM part number 27-807218 from your engine's service manual with our listing.
What causes an exhaust manifold end cap gasket to fail?
Failure is often due to age, heat cycles, corrosion from raw water cooling, or improper installation (uneven torque). Signs of failure include water leaks from the end cap area, rust stains, engine overheating, or rough running.
Is any sealant required when installing this gasket?
This gasket is typically designed for a dry installation. Applying sealants can sometimes cause the gasket to slip during installation, leading to leaks. Always consult your engine's official service manual for guidance on using sealants.
Is this an OEM or aftermarket part?
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.
What are the shipping speed and cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
What is the warranty and return policy?
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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