Powerhead Gasket Set – Fits Mercury/Mariner 3.0L 200-250HP Engines (Replaces 27-832934A00)
Powerhead Gasket Set – Fits Mercury/Mariner 3.0L 200-250HP Engines (Replaces 27-832934A00) 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
Powerhead Gasket Set – Fits Mercury/Mariner 3.0L 200-250HP Engines ...
Product Details
This complete Powerhead Gasket Set is designed for Mercury and Mariner 3.0L V6 EFI and DFI/Optimax engines, covering models from 200 HP to 250 HP manufactured between 2000 and 2018. It provides all the essential seals and gaskets required for a comprehensive powerhead service, ensuring a reliable seal and restoring engine integrity.
This kit serves as a direct replacement for Mercury part number 27-832934A00 / 832934A00 and aftermarket equivalent WSM 500-245.
- Includes critical components like crankshaft seals, cap O-rings, and cylinder head seals.
- Engine-specific fitment; professional installation is highly recommended.
- Designed for use with gasoline (EFI and DFI) engines.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 27-832934A00 |
| Mercury | 832934A00 |
| WSM | 500-245 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This set is compatible with a wide range of Mercury and Mariner 3.0L V6 outboards.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | 200 (3.0L DFI)(DTS) | 200 | 4-Stroke | 2000–2018 | 27-832934A00 | Various serial ranges: 0T980000-1B417701, 1B417702-1B504988, 1B504989 & Up |
| Mercury | 200 (3.0L EFI) | 200 | 4-Stroke | 2000–2008 | 27-832934A00 | Various serial ranges: 0T750164-0T800999, 0T801000-1B417701, 1B417702-1B504988, 1B504989 & Up |
| Mercury | 200 (DFI) Optimax | 200 | 2-Stroke | 2000–2018 | 27-832934A00 | Various serial ranges: 0G960500-0T178499, 0T178500-0T598999, 0T599000-0T800999 |
| Mercury | 200 PRO XS (DFI) 3.0L | 200 | 2-Stroke | 2008–2018 | 27-832934A00 | Serial ranges: 1B504989-1B912785, 1B912786 & Up |
| Mercury | 225 (3.0L EFI) | 225 | 4-Stroke | 2000–2008 | 27-832934A00 | Various serial ranges: 0T409000-0T800999, 0T801000-1B417701, 1B417702-1B504988, 1B504989 & Up |
| Mercury | 225 (3.0L EFI) MARATHON | 225 | 4-Stroke | 2000–2008 | 27-832934A00 | Serial range: 0T801000-1B417701 |
| Mercury | 225 (3.0L EFI) SEAPRO | 225 | 4-Stroke | 2000–2008 | 27-832934A00 | Serial range: 0T801000-1B417701 |
| Mercury | 225 (3.0L-DFI)(DTS) | 225 | 2-Stroke | 2000–2018 | 27-832934A00 | Various serial ranges: 0T599000-1B417701, 1B417702-1B504988, 1B504989 & Up |
| Mercury | 225 (DFI) Optimax | 225 | 2-Stroke | 2000–2018 | 27-832934A00 | Various serial ranges: 0G960500-0T178499, 0T178500-0T598999, 0T599000-0T800999 |
| Mercury | 250 (3.0L EFI) | 250 | 4-Stroke | 2000–2008 | 27-832934A00 | Various serial ranges: 0T409000-0T800999, 0T801000-1B417701, 1B417702-1B504988, 1B504989 & Up |
| Mercury | 250 (DFI) 3.0L | 250 | 2-Stroke | 2008–2014 | 27-832934A00 | Serial range: 1B528615 & Up |
| Mercury | 250 LONG (3.0L)(EFI) | 250 | 4-Stroke | 2002–2008 | 27-832934A00 | Serial range: 0T861319 & Up |
| Mercury | 3.0L EFI MARATHON | 200-250 | 4-Stroke | 2000–2008 | 27-832934A00 | Serial range: 0T409000-0T800999 |
| Mercury | 3.0L EFI SEAPRO | 200-250 | 4-Stroke | 2000–2008 | 27-832934A00 | Serial range: 0T409000-0T800999 |
| Mercury | 250 PRO XS (3.0L) | 250 | 2-Stroke | 2008–2018 | 27-832934A00 | Includes DFI models |
Technical Specs
- Product Type
- Complete Powerhead Gasket Set
- Installation
- Engine-specific; professional installation recommended
- Fuel Type
- Gasoline (for EFI and DFI engines)
- Dimensions
- 40.0" L × 23.5" W × 1.0" H (1016 × 597 × 25.4 mm)
- Weight
- 0.81 lb (0.37 kg)
- Other Technical Attributes
- Includes crankshaft seals, cap O-rings, and cylinder head seals
What’s in the Box
- 1 x Cylinder Head Seals (includes yellow "tall" ring cylinder seals OE: 25-884391)
- 1 x Crankshaft Seals
- 1 x Cap O-rings
Installation Notes
- Disconnect the battery and relieve fuel system pressure before beginning work. Ensure the engine is cool.
- Carefully disassemble the engine components required to access the powerhead, labeling all parts and fasteners.
- Thoroughly clean all mating surfaces of old gasket material, oil, and debris. Use a plastic scraper and appropriate solvent to avoid gouging aluminum surfaces.
- Compare the new gaskets to the old ones to ensure a perfect match for all ports and bolt holes.
- Install the new gaskets and seals, following the manufacturer's service manual for correct placement and orientation.
- Reassemble the powerhead, tightening all bolts in the specified sequence and to the correct torque values. Incorrect torque can lead to leaks and engine damage.
- After reassembly, reconnect all systems. Run the engine and carefully check for any fuel, oil, or coolant leaks before returning to service.
Troubleshooting & FAQ
How do I confirm this gasket set will fit my exact engine model?
The most reliable way is to verify your engine's model, year, and serial number against our compatibility table. Pay close attention to the serial number ranges listed in the 'Notes' column, as fitment can be specific.
Does this kit include every single gasket for a full powerhead rebuild?
This is a comprehensive powerhead gasket set that includes all essential gaskets, O-rings, and seals for the main assembly, including cylinder head and crankshaft seals. However, depending on the specific service being performed, other individual gaskets not part of the main powerhead assembly may be required.
What are the signs of a leaking powerhead or cylinder head gasket?
Common symptoms include loss of compression on one or more cylinders, water in the oil (milky appearance), oil in the water, engine overheating, and a noticeable loss of power. A compression test is a key diagnostic step.
Why is professional installation recommended?
Proper installation requires specialized tools, a clean environment, and adherence to strict torque specifications and sequences from a service manual. Mistakes during installation can lead to immediate leaks or catastrophic engine failure.
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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