Exhaust Manifold Gasket – Fits Mercury/Mercruiser 3.0L 4-Cylinder Engines (Replaces 27-815528)
Exhaust Manifold Gasket – Fits Mercury/Mercruiser 3.0L 4-Cylinder Engines (Replaces 27-815528) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Exhaust Manifold Gasket – Fits Mercury/Mercruiser 3.0L 4-Cylinder E...
Product Details
This is a direct replacement Exhaust Manifold Gasket designed for 4-cylinder marine engines. It is compatible with Mercury/Mercruiser 3.0L models from 1990 to the present and OMC/Volvo Penta 3.0L GM engines from 1991 and newer using small exhaust port configurations.
This gasket serves as a direct interchange for Mercury 27-815528, OMC 3853256, Volvo Penta 3853256, Sierra 18-0680, and GLM 33580.
- Engineered for direct-fit installation, connecting the exhaust manifold to the cylinder head.
- Constructed from a durable paper-based composite to ensure a reliable seal against exhaust gases.
- Designed specifically for gasoline marine engine environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 27-815528 |
| OMC | 3853256 |
| Volvo Penta | 3853256 |
| Sierra | 18-0680 |
| GLM | 33580 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury/Mercruiser engines, this gasket fits 3.0L models from 1990 to present, including 3.0LX, 3.0L MPI EC, and 3.0L TKS Plus variants. Check your serial number against the ranges provided.
For OMC and Volvo Penta, this part is used on 3.0L GM 181 CID engines from 1991 and newer with small exhaust port configurations.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercruiser | 3.0L GM 181 I/L4 | 140 | 4-Stroke | 1998–present | 27-815528 | 0L097000 & up |
| Mercruiser | 3.0LX GM 181 I/L4 | 140 | 4-Stroke | 1990–1997 | 27-815528 | 0C856559 thru 0K999999 |
| Mercruiser | 3.0L MPI EC | 140 | 4-Stroke | 1A072812 & up | 27-815528 | |
| Mercruiser | 3.0L TKS Plus | 140 | 4-Stroke | 1G404114 & up | 27-815528 | |
| OMC/Volvo Penta | 3.0L GM 181 CID | 140 | 4-Stroke | 1991 & newer | 3853256 | Small exhaust ports |
Technical Specs
- Product Type
- Exhaust Manifold Gasket
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Connection
- Exhaust manifold to cylinder head
- Housing Material
- Paper-based composite
- Housing Color
- Black/Gray
- Dimensions
- 52.0 L × 13.0 W × 1.0 H
- Weight
- 0.05 kg (0.13 lb)
- Fitting Type
- Direct fit
- Warranty
- Manufacturer standard warranty
- Other Technical Attributes
- Used for sealing exhaust gases between the exhaust manifold and cylinder head
What’s in the Box
- 1 x Exhaust Manifold Gasket (27-815528)
Installation Notes
- Disconnect the battery and allow the engine to cool completely before starting.
- Drain the engine coolant to prevent spills when the manifold is removed.
- Carefully detach all connections to the exhaust manifold, including sensors and exhaust pipes.
- Unbolt and remove the old exhaust manifold. You may need a pry bar if it is stuck.
- Thoroughly clean the mating surfaces on both the cylinder head and the manifold. Ensure all old gasket material and carbon deposits are removed.
- Position the new gasket correctly. Do not use any sealant unless specified by the engine manufacturer.
- Reinstall the exhaust manifold and tighten the bolts in the sequence and to the torque specifications recommended by the manufacturer.
- Reconnect all sensors and pipes, refill the coolant, and reconnect the battery.
- Start the engine and carefully check for any exhaust or coolant leaks around the manifold.
Troubleshooting & FAQ
How do I confirm this gasket fits my specific engine?
The surest way is to match your engine's model, year, and serial number against our compatibility table. You can also verify the OEM part number (like 27-815528 for Mercury) required for your engine, often found in your service manual or by looking up your serial number online.
What are the signs of a failing exhaust manifold gasket?
Common symptoms include a ticking or tapping noise from the engine bay that is more noticeable on a cold start, reduced engine performance, poor fuel economy, and the smell of exhaust fumes inside the boat or engine compartment.
Can I reuse my old exhaust manifold gasket?
No. Gaskets are single-use components designed to crush and seal upon installation. Reusing an old gasket will almost certainly result in leaks, poor performance, and potential damage to engine components.
Is any sealant required when installing this gasket?
This gasket is designed to be installed dry. Applying sealants can interfere with its ability to seal properly and may cause premature failure. Always follow the engine manufacturer's service manual for specific instructions.
What is the recommended replacement interval for this part?
There is no fixed replacement interval. Gaskets should be replaced whenever the exhaust manifold is removed for service or if you notice any signs of failure, such as exhaust leaks.
Why is the part number different for Mercury and OMC/Volvo?
While the gasket may be dimensionally identical for certain engine applications, different manufacturers (like Mercury, OMC, and Volvo Penta) assign their own unique part numbers for tracking and inventory. This part is cross-compatible with all listed OEM numbers.
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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