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SeaSierra

Cylinder Head Gasket – Fits Yamaha V6 90° 150–225HP Outboards (Replaces 6G5-11181-A3-00)

$54.53 $87.00
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Cylinder Head Gasket – Fits Yamaha V6 90° 150–225HP Outboards (Replaces 6G5-11181-A3-00) is backordered and will ship as soon as it is back in stock.

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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

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This high-quality aftermarket Cylinder Head Gasket is designed to fit a wide range of Yamaha 2-Stroke V6 90° outboard engines from 150HP to 225HP, manufactured between 1984 and 2009. It is fully compatible with both carbureted and EFI models, including Saltwater Series (SX), Commercial (C), and Long Shaft (L) variants, ensuring a precise seal for optimal engine performance.

It serves as a direct replacement for Yamaha OEM part numbers 6G5-11181-A3-00, 6G5-11181-A2-00, 6G5-11181-A1-00, 6G5-11181-A0-00, 6G5-11181-01-00, and 6G5-11181-00-00.

  • Engineered for direct replacement, though installation requires following the proper torque sequence for your engine.
  • Effectively maintains proper compression and prevents leakage between the cylinder head and the engine block.
  • Built to withstand the harsh marine environment, ensuring reliability and longevity.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket parts.

Brand Part Number Superseded By Notes
Yamaha 6G5-11181-00-00 6G5-11181-01-00 Original Part
Yamaha 6G5-11181-01-00 6G5-11181-A0-00 Supersession
Yamaha 6G5-11181-A0-00 6G5-11181-A1-00 Supersession
Yamaha 6G5-11181-A1-00 6G5-11181-A2-00 Supersession
Yamaha 6G5-11181-A2-00 6G5-11181-A3-00 Supersession
Yamaha 6G5-11181-A3-00 - Current Active Part Number

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This gasket is designed exclusively for a wide range of Yamaha V6 outboard models. Please check your specific model and year against the list to ensure correct fitment.

Brand Model Rated HP Stroke Years Notes
Yamaha 150TXR 150 2-Stroke 2003–2009
Yamaha 150TXRB/C/D 150 2-Stroke 2003–2005
Yamaha V150TLR 150 2-Stroke 2003–2008
Yamaha V150TLRB/C/D 150 2-Stroke 2003–2005
Yamaha VX150TLRB/C 150 2-Stroke 2003–2004
Yamaha DX150TLRB/C/D 150 2-Stroke 2003–2005
Yamaha SX150TXRB/C 150 2-Stroke 2003–2004
Yamaha SX200TXRB/C/D 200 2-Stroke 2003–2005
Yamaha 150ETLH/J 150 2-Stroke 1986–1987
Yamaha 150ETXH/J 150 2-Stroke 1986–1987
Yamaha 150TJRV/W/X/Y 150 2-Stroke 1997–2000
Yamaha 150TLRV/W/Y 150 2-Stroke 1997–2000
Yamaha 150TXRA/Y/Z 150 2-Stroke 2000–2002
Yamaha 175ETLH/J 175 2-Stroke 1986–1987
Yamaha 175ETXH/J 175 2-Stroke 1986–1987
Yamaha 175TLRY 175 2-Stroke 2000
Yamaha 175TXRY 175 2-Stroke 2000
Yamaha 200ETLH/J 200 2-Stroke 1986–1987
Yamaha 200ETXH/J 200 2-Stroke 1986–1987
Yamaha 200TLRV/W 200 2-Stroke 1997–1998
Yamaha 225TLRU/V 225 2-Stroke 1996–1997
Yamaha C150TLRU/V/W/X 150 2-Stroke 1996–1999 Commercial series
Yamaha C150TXRU/V/W/X 150 2-Stroke 1996–1999 Commercial series
Yamaha D150TLRV/W/X 150 2-Stroke 1997–1999
Yamaha DX150TLRA/X/Y/Z 150 2-Stroke 1999–2002
Yamaha L150TXRV/W/X 150 2-Stroke 1997–1999 Long shaft
Yamaha L200TXRV/W/X 200 2-Stroke 1997–1999 Long shaft
Yamaha LX150TXRX/Y/Z 150 2-Stroke 1999–2001
Yamaha LX200TXRCX/X/Y/Z 200 2-Stroke 1999–2001
Yamaha P150TLRV/W/X 150 2-Stroke 1997–1999
Yamaha P175TLRV/W/X 175 2-Stroke 1997–1999
Yamaha P200TLRV/W/X 200 2-Stroke 1997–1999
Yamaha PROV150LH 150 2-Stroke 1987
Yamaha PX150TLRX 150 2-Stroke 1999
Yamaha S150TLRV/W/X 150 2-Stroke 1997–1999
Yamaha S150TXRV/W/X 150 2-Stroke 1997–1999
Yamaha S175TXRV/W/X 175 2-Stroke 1997–1999
Yamaha S200TXRV/W/X 200 2-Stroke 1997–1999
Yamaha SX150TLRX/Y 150 2-Stroke 1999–2000
Yamaha SX150TXRA/X/Y/Z 150 2-Stroke 1999–2002
Yamaha SX200TXRA/X/Y/Z 200 2-Stroke 1999–2002
Yamaha V150TLRA/Y/Z 150 2-Stroke 2000–2002
Yamaha V175TLRY 175 2-Stroke 2000
Yamaha VX150TLRA/Y/Z 150 2-Stroke 2000–2002
Yamaha 150ETLD/DA/F/K/N 150 2-Stroke 1984–1990
Yamaha 150ETXD/DA/F/K/N 150 2-Stroke 1984–1990
Yamaha 150TJRS/T/U 150 2-Stroke 1994–1996
Yamaha 150TLRP/Q/R/S/T/U 150 2-Stroke 1991–1996
Yamaha 150TXRP/Q/R/S/T 150 2-Stroke 1991–1995
Yamaha 175ETLD/DA/F/K/N 175 2-Stroke 1984–1990
Yamaha 175ETXD/DA/F/K/N 175 2-Stroke 1984–1990
Yamaha 175TLRP/Q/R/S/T 175 2-Stroke 1991–1995
Yamaha 175TXRP/Q/R/S/T 175 2-Stroke 1991–1995
Yamaha 200ETLD/DA/F/K/N 200 2-Stroke 1984–1990
Yamaha 200ETXD/DA/F/K/N 200 2-Stroke 1984–1990
Yamaha 200TJRP/Q/R/S/T 200 2-Stroke 1991–1995
Yamaha 200TLRP/Q/R/S/T/U 200 2-Stroke 1991–1996
Yamaha 200TXRP/Q/R/S/T 200 2-Stroke 1991–1995
Yamaha 225ETLD/DA 225 2-Stroke 1990
Yamaha 225ETXD/DA 225 2-Stroke 1990
Yamaha 225TLRP/Q/R/S/T 225 2-Stroke 1991–1995
Yamaha 225TXRP/Q/R 225 2-Stroke 1991–1993
Yamaha L150ETXD/DA/F/G/H/J 150 2-Stroke 1986–1990 Long shaft
Yamaha L150TXRP/Q/R/S/T/U 150 2-Stroke 1991–1996 Long shaft
Yamaha L200ETXD/DA/F/G/H/J 200 2-Stroke 1986–1990 Long shaft
Yamaha L200TXRP/Q/R/S/T/U 200 2-Stroke 1991–1996 Long shaft
Yamaha P150TLRP/Q/R/S/T/U 150 2-Stroke 1991–1996
Yamaha P175TLRS/T/U 175 2-Stroke 1994–1996
Yamaha P200TLRP/Q/R/S/T/U 200 2-Stroke 1991–1996
Yamaha PROV150J/LD/DA/F/G/H/J 150 2-Stroke 1986–1990
Yamaha S150TLRU 150 2-Stroke 1996
Yamaha S150TXRU 150 2-Stroke 1996
Yamaha S175TXRU 175 2-Stroke 1996
Yamaha S200TXRU 200 2-Stroke 1996
Yamaha V6EXCELLF/G/H 150-200 2-Stroke 1987–1989
Yamaha V6EXCELXF/G/H 150-200 2-Stroke 1987–1989
Yamaha V6SPECIALLJ/K/N 150-200 2-Stroke 1984–1986
Yamaha V6SPECIALXJ/K/N 150-200 2-Stroke 1984–1986

Technical Specs

Product Type
Cylinder Head Gasket
Application
90° V6 Yamaha outboard engines
Material
Steel
Dimensions
44.5cm x 17.5cm x 1.0cm (L x W x H)
Compatibility
Carbureted and EFI models
Quality
High-quality aftermarket replacement
Function
Maintains proper compression and cooling system separation

What’s in the Box

  • 1 x Cylinder Head Gasket (Replaces 6G5-11181-A3-00)

Installation Notes

  1. Disconnect the battery and drain the engine's cooling system completely.
  2. Carefully remove the cylinder head cover and any interfering components.
  3. Remove the old head gasket and thoroughly clean both the cylinder head and engine block surfaces. Ensure they are free of any old gasket material, oil, or debris.
  4. Position the new gasket correctly on the engine block; do not use any sealant unless specified by the manufacturer.
  5. Reinstall the cylinder head and tighten the bolts in the specific sequence and to the torque values listed in your engine's service manual. This step is critical.
  6. Reconnect all components, refill the cooling system, and reconnect the battery.
  7. Start the engine and carefully check for any coolant or exhaust leaks around the cylinder head.

Troubleshooting & FAQ

How do I know if my cylinder head gasket is failing?

Common signs of a blown head gasket include engine overheating, a noticeable loss of power or compression, milky-white residue in the engine oil (indicating coolant contamination), white smoke from the exhaust, or visible coolant leaks from the engine.

Do I need special tools for this installation?

A calibrated torque wrench is essential. Tightening the head bolts to the correct specification and in the proper sequence is critical for a successful seal and to prevent engine damage. Always refer to your engine's service manual.

Is this gasket for one or both cylinder heads on a V6?

This is for a single gasket. V6 engines have two cylinder banks and require two separate head gaskets. You must purchase two units to replace both.

Why is the torque sequence so important?

The torque sequence ensures that pressure is applied evenly across the entire surface of the gasket as the cylinder head is tightened. This prevents warping the head and ensures a complete, durable seal. An incorrect sequence will lead to premature gasket 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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