Power Head Gasket Kit – Fits Yamaha/Mercury F30/F40 4-Stroke (67C-W0001-01-00, 825231A02)

$302.92

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Product Details

This aftermarket Power Head Gasket Kit is designed for a complete top-end engine overhaul. It fits specific 3-cylinder, 4-stroke Yamaha F30/F40 models from 2000–2009 and Mercury 30/40 HP models from 2001–2021.

It serves as a direct replacement for Yamaha part numbers 67C-W0001-00-00, 67C-W0001-01-00, 67C-W0001-02-00; Mercury equivalents 825231A02, 27-825231A99, 27-859352A02; and Sierra 18-99092.

Engineered for direct OEM replacement fit and function.
Includes a complete set of gaskets and seals for cylinder head service.
Designed for use with standard gasoline outboards.

Part Number Matrix

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

Brand	Part Number
Yamaha	67C-W0001-00-00
Yamaha	67C-W0001-01-00
Yamaha	67C-W0001-02-00
Mercury	825231A02
Mercury	27-825231A99
Mercury	27-859352A02
Sierra	18-99092

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Yamaha engines, this kit is compatible with all F30 and F40 4-stroke variants manufactured between 2000 and 2009.

For Mercury engines, this kit fits 30 and 40 HP 4-stroke models with serial numbers from OP153500 to OP400999.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Yamaha	F30	30	4-Stroke	2000–2009	67C-W0001-01-00	All variants including A, B, ERA, BEDL, ELHB, BET, ELHC, TR, BWMHT, ELHF, BMHD, MLHA, AET, AMHD
Yamaha	F40	40	4-Stroke	2000–2009	67C-W0001-01-00	All variants including EJR, MJH, MLH, MSH, TLR
Mercury	30	30	4-Stroke	2001–2021	825231A02	Serial numbers OP153500-OP400999
Mercury	40	40	4-Stroke	2001–2021	825231A02	Serial numbers OP153500-OP400999

Technical Specs

Product Type: Outboard Power Head Gasket Kit
Installation: OEM Replacement
Fuel Type: Gasoline
Housing Material: Various (Gasket materials)
Warranty: 1 Year (based on Oversee aftermarket equivalent)
Other Technical Attributes: Complete gasket kit for cylinder head service
Product Dimensions: 12.0" L x 8.0" W x 1.0" H

What’s in the Box

1 x Power Head Gasket Kit (67C-W0001-01-00)
1 x Gasket (663) (90430-14115-00)
1 x Gasket, Cylinder (67C-11351-01-00)
1 x Gasket (62Y-12414-01-00)
1 x Gasket, Exhaust Outer Cover (67C-41114-10-00)
1 x Oil Seal (62Y) (93102-43M42-00)
1 x Oil Seal (62Y) (93102-35M47-00)
4 x Gasket (90430-06014-00)
1 x Gasket, Cylinder Head 1 (67C-11181-01-00)
1 x Seal, Cylinder 2 (67C-11356-00-00)
2 x O-Ring (93210-24235-00/93210-25070-00)
9 x O-Ring (67C-14561-00-00)
3 x O-Ring (67C-14562-00-00)
3 x O-Ring (93210-34MJ6-00)
1 x Oil Seal (62Y) (93102-37M40-00)
1 x Key, Woodruff (6A1) (90280-04M06-00)
1 x O-Ring (62Y) (93210-33MH2-00)
1 x O-Ring (62Y) (93210-12MG9-00)
1 x O-Ring (11H) (93210-14515-00)

Installation Notes

Disconnect the battery and relieve any pressure in the fuel system.
Drain the engine oil and coolant completely.
Remove all external components blocking access to the power head and cylinder head.
Carefully detach the power head assembly from the engine's midsection.
Disassemble the power head, keeping all bolts and smaller components organized.
Thoroughly clean all mating surfaces to remove old gasket material and any sealant residue.
Ensure all surfaces are perfectly flat, clean, and dry before installing new gaskets.
Install the new gaskets and seals from the kit. Do not use additional sealant unless specified by your engine’s official service manual.
Reassemble the power head, torquing all bolts to the manufacturer’s specifications in the correct sequence.
Reinstall the power head, reconnect all components, and refill the engine with fresh oil and coolant.
Before starting the engine, check carefully for any signs of fuel, oil, or coolant leaks.

Troubleshooting & FAQ

How do I know if I need a new power head gasket kit?

Common signs of a failed head gasket include milky or discolored engine oil (indicating water/coolant mixing), frequent engine overheating, loss of compression, or visible leaks between the cylinder head and engine block.

Is this kit for 2-stroke or 4-stroke engines?

This kit is specifically designed for the 4-Stroke, 3-cylinder Yamaha F30/F40 and Mercury 30/40 HP models listed in the compatibility table. It is not suitable for 2-stroke engines.

Do I need to use sealant with these gaskets?

Generally, no. These gaskets are designed to seal on their own. Only apply sealant if it is explicitly recommended for a specific area in the OEM service manual for your engine.

What is the difference between this kit and an OEM kit?

This aftermarket kit is engineered to meet or exceed OEM specifications using comparable, high-quality materials. It provides a cost-effective, reliable alternative for engine repairs.

The kit has many parts. Will I use them all?

This kit is designed to cover multiple engine models and years. It is common to have a few extra O-rings or seals left over. Use the parts that match the ones you are replacing.

Can I reuse any of my old gaskets or seals?

No. Never reuse old gaskets or seals, especially in a critical application like a power head. Always replace them to ensure a proper, lasting seal and prevent engine damage.

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

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