Poppet Valve Gasket – Fits Mercury/Mariner 30–60 HP Outboards (Replaces 27-8128672)

$5.17

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Product Details

This aftermarket Poppet Valve Gasket is engineered for use in a wide variety of Mercury and Mariner 2-stroke outboard engines, primarily in the 30–60 HP range. It ensures a proper seal for the poppet valve assembly, which is critical for maintaining correct engine operating temperature.

This part serves as a direct cross-reference for Mercury original equipment part numbers 27-8128672 and 8128672.

Installation Method: Direct replacement for the original OEM gasket.
Operating Environment: Designed for use in marine gasoline engines.
Quality Standard: Built to meet or exceed OEM specifications for fit and function.

Part Number Matrix

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

Brand	Part Number	Notes
Mercury	27-8128672	Original Equipment Reference
Mercury	8128672	Original Equipment Reference

Engine & Model Compatibility

Confirm your engine model and serial number range in the table below to ensure accurate fitment.

For Mercury/Mariner Engines: This gasket fits numerous 2-stroke models from 30 HP to 60 HP, including specific serial number ranges for standard, JET, and BIGFOOT configurations. Please verify your engine's details against the list.

Brand	Model	Rated HP	Stroke	OEM Part No.
Mercury	30 (2 CYL.)	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 0G055314 THRU 0G760299	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 0G760300 THRU 0T979999	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 0P017000 THRU 0P325499	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 0P325500 & Up	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 0T980000 THRU 0T999999	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 1B000001 & Up	30	2-Stroke	27-8128672
Mercury	30 (2 CYL.) - 9854537 THRU 0P016999	30	2-Stroke	27-8128672
Mercury	40 (2 CYL.)	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 0G055314 THRU 0G760299	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 0G760300 THRU 0T979999	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 0P017000 THRU 0P325499	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 0P325500 & Up	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 0T980000 THRU 0T999999	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 1B000001 & Up	40	2-Stroke	27-8128672
Mercury	40 (2 CYL.) - 9854537 THRU 0P016999	40	2-Stroke	27-8128672
Mercury	40 JET - 0P325500 & Up	40 JET	2-Stroke	27-8128672
Mercury	40 JET - 0T980000 & Up	40 JET	2-Stroke	27-8128672
Mercury	40 JET - 0P094500 THRU 0P325499	40 JET	2-Stroke	27-8128672
Mercury	40 JET - 0T178500 THRU 0T979999	40 JET	2-Stroke	27-8128672
Mercury	45 JET - 0D000750 THRU 0G290584	45 JET	2-Stroke	27-8128672
Mercury	45 JET - 0G290585 THRU 0G589999	45 JET	2-Stroke	27-8128672
Mercury	45 JET - 0G760300 THRU 0T129554	45 JET	2-Stroke	27-8128672
Mercury	45 JET - 0P017000 THRU 0P094499	45 JET	2-Stroke	27-8128672
Mercury	45 JET - 9683055 THRU 9885344	45 JET	2-Stroke	27-8128672
Mercury	45 JET - 9885385 THRU 9973099	45 JET	2-Stroke	27-8128672
Mercury	50 (3 CYL.) - 0D000750 THRU 0G290584	50	2-Stroke	27-8128672
Mercury	50 (3 CYL.) - 0G290585 THRU 0G589999	50	2-Stroke	27-8128672
Mercury	50 (3 CYL.) - 9683055 THRU 9885344	50	2-Stroke	27-8128672
Mercury	50 (3 CYL.) - 9885345 THRU 9973099	50	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0D000750 THRU 0G290584	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0G290585 THRU 0G589999	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0G760300 THRU 0T979999	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0P017000 THRU 0P325499	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0P325500 & Up	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 0T980000 & Up	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 9741042 THRU 9885344	55	2-Stroke	27-8128672
Mercury	55 (3 CYL.) - 9885345 THRU 9973099	55	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0D000750 THRU 0G290584	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0G290585 THRU 0G589999	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0G760300 THRU 0T979999	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0P017000 THRU 0P325499	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0P325500 & Up	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 0T980000 & Up	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 9683055 THRU 9885344	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) - 9885345 THRU 9973099	60	2-Stroke	27-8128672
Mercury	60 (3 CYL.) BIGFOOT - 0G760300 THRU 0T979999	60 BIGFOOT	2-Stroke	27-8128672
Mercury	60 (3 CYL.) BIGFOOT - 0P017000 THRU 0P325499	60 BIGFOOT	2-Stroke	27-8128672

Technical Specs

Product Type: Poppet Valve Gasket
Design: Aftermarket part built to OEM specifications
Installation: Direct OEM replacement
Fuel Type: Compatible with gasoline engines
Dimensions: Length: 16.0 in (406.4 mm), Width: 11.5 in (292.1 mm), Height: 0.1 in (2.54 mm)
Weight: 0.08 lb (0.036 kg)

What’s in the Box

1x Poppet Valve Gasket (Replaces 27-8128672/8128672)

Installation Notes

Always consult your engine’s service manual for detailed procedures. The following are general, model-agnostic steps:

Ensure the engine is off and the battery is disconnected.
Drain the cooling system sufficiently to access the poppet valve assembly without spillage.
Locate the poppet valve cover, unbolt it, and carefully remove the old gasket.
Thoroughly clean both the cover and the engine block mating surfaces. Remove all old gasket material and corrosion.
Position the new gasket correctly on the engine block or cover.
Reinstall the cover and tighten the bolts to the manufacturer's specified torque in the correct sequence.
Refill the cooling system, reconnect the battery, and run the engine while checking for leaks.

Troubleshooting & FAQ

How do I confirm this gasket fits my specific engine model?

The most reliable method is to cross-reference your engine's model, year, and serial number against the compatibility table in this listing. If your model is listed, the part is a confirmed fit.

What are the signs of a leaking or failed poppet valve gasket?

Common symptoms include the engine overheating at idle or low RPMs, but running at a normal temperature at high RPMs. You may also see visible water leaking from the poppet valve cover area.

Is any adhesive or sealant required for installation?

Typically, this type of gasket is designed to be installed dry. Applying sealant can sometimes interfere with a proper seal. However, always refer to your specific engine's service manual for the definitive recommendation.

What does the poppet valve do in my outboard motor?

The poppet valve regulates cooling water pressure inside the engine block. At low speeds, it remains closed to help the engine warm up and maintain proper temperature. As RPMs increase, it opens to allow more water flow, preventing overheating.

Can I reuse my old gasket?

No. Gaskets are single-use components that compress and deform to create a seal. Once removed, they will not provide a reliable seal and should always be replaced with a new one.

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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