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Reed Plate Gasket – Fits Mercury/Mercruiser (27-883775)

Regular price $19.99
Shipping calculated at checkout.

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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).

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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 aftermarket Reed Plate Gasket is a direct-fit replacement for various Mercury Marine EFI Jet Drive applications. It is designed to create a reliable seal between the reed plate and the cylinder block, which is essential for maintaining engine performance and preventing air leaks.

It serves as a direct interchange for Mercury OEM part numbers 27-883775, 881034, and 813859.

  • Installs between the reed plate and cylinder block.
  • Engineered to meet or exceed original factory specifications.
  • Includes one gasket for a complete single-component replacement.

Part Number Matrix

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

Brand Part Number Notes
Mercury Marine 27-883775 Current Part
Mercury Marine 881034 Superseded by 27-883775
Mercury Marine 813859 Superseded by 27-883775

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury Marine engines, please verify your model and serial number against the ranges specified below to ensure correct fitment.

Brand Model Rated HP OEM Part No. Notes
Mercury 240 EFI JET DRIVE (POWERHEAD) 240 27-883775 Serial range: 0E384500 THRU 0E406399 - USA
Mercury 240 EFI JET DRIVE (PUMP) 240 27-883775 Serial range: 0E379931 THRU 0E406399 - USA
Mercury 240 EFI M2 JET DRIVE (POWERHEAD) 240 27-883775 Serial range: 0E384500 THRU 0E406399 - USA
Mercury 240 EFI M2 JET DRIVE (PUMP) 240 27-883775 Serial range: 0E379931 THRU 0E406399 - USA

Technical Specs

Product Type
Reed Plate Gasket
Installation Location
Between reed plate and cylinder block
Dimensions (L x W x H)
41.5 x 20.0 x 0.5 cm
Weight
0.043 kg (0.09 lb)
OEM Brand
Mercury Marine
Part Number
27-883775
Supersedes
881034, 813859
GTIN
745061481589

What’s in the Box

  • 1 x Gasket (27-883775)

Installation Notes

  1. Ensure the engine is off and cool, and disconnect the battery as a safety precaution.
  2. Gain access to the reed plate assembly. This may require removing the carburetor or intake manifold.
  3. Carefully remove the bolts securing the reed plate to the cylinder block and detach the assembly.
  4. Thoroughly clean the mating surfaces on both the cylinder block and the reed plate. Remove all traces of old gasket material and debris.
  5. Position the new gasket correctly over the cylinder block dowels.
  6. Reinstall the reed plate assembly and tighten the bolts in a crossing pattern to the manufacturer-specified torque values.
  7. Reconnect all previously removed components and the battery, then check for proper engine operation and air leaks.

Troubleshooting & FAQ

How do I know if my reed plate gasket needs replacing?

Signs of a failed reed plate gasket include poor or rough idling, a loss of engine power, difficulty starting, or backfiring. A visual inspection may also reveal cracks, brittleness, or breaks in the old gasket material.

Is this gasket compatible with all Mercury 240 HP engines?

No. This part is specifically for the Mercury 240 HP models designated as EFI Jet Drive or EFI M2 Jet Drive. It is critical to match your engine's serial number to the ranges listed in the compatibility table to ensure a proper fit.

What is the function of a reed plate gasket?

This gasket creates an airtight seal between the reed plate and the engine's cylinder block. This seal is vital for maintaining correct crankcase pressure, which allows the reed valves to function properly and ensures efficient engine combustion.

Can I reuse an old gasket?

No. Gaskets are designed for a single use; they compress to create a seal and lose their effectiveness once removed. Reusing a gasket will almost certainly lead to air leaks, poor performance, and potential engine damage.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, it is batch-inspected for consistency.

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Shipping speed & cost

We ship worldwide quickly—typical transit is 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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